West Sumatra (Indonesian: Sumatera Barat) is a province of Indonesia. It is on the west coast of the island of Sumatra and includes the Mentawai Islands off that coast. West Sumatra borders the Indian Ocean to the west, as well as the provinces of North Sumatra to the north, Riau to the northeast, Jambi to the southeast, and Bengkulu to the south. The province has an area of 42,119.54 km (16,262.45 sq mi), or about the same size as Switzerland, with a population of 5,534,472 at the 2020 census. The official estimate at mid 2023 was 5,757,210 (comprising 2,900,270 males and 2,856,940 females). The province is subdivided into twelve regencies and seven cities. It has relatively more cities than other provinces outside Java, although several of them are relatively low in population compared with cities elsewhere in Indonesia. Padang is the province's capital and largest city.

West Sumatra is home to the Minangkabau people, although the traditional Minangkabau region is actually wider than the province's boundaries, covering up to the western coast of North Sumatra, the southwestern coast of Aceh, the western region of Riau, the western region of Jambi, the northern region of Bengkulu, and Negeri Sembilan in Malaysia. Another native ethnic group is the Mentawai people, who inhabit the western islands of the same name. Islam is a predominant religion in the province, with about 97.4% of the total population.

West Sumatra was the centre of the Pagaruyung Kingdom, founded by Adityawarman in 1347. The first European to come to the region was a French traveler named Jean Parmentier who arrived around 1523. The region was later colonised by the Dutch Empire and became a residency named Sumatra's West Coast (Dutch: Sumatra's Westkust), whose administrative area included the present-day Kampar Regency in Riau and Kerinci Regency in Jambi. Before becoming a province in 1957, West Sumatra was a part of the province of Central Sumatra (1948–1957), alongside Riau, Jambi, and the Riau Islands.

West Sumatra is known by the name Bumi Minangkabau (Land of Minangkabau), as it is the home and origin of the Minangkabau people. The Minangkabau name comes from two words namely, Minang (win) and Kabau (cattle). The name is associated with a Minangkabau legend known as Tambo. From the Tambo, it is said that at one time there was a foreign kingdom (usually interpreted as the Majapahit Empire) which came from the sea and would conquer what is now West Sumatra. To prevent fighting in the region, the local people propose a cattle race competition with the foreign forces. The foreign forces agreed and sent a large and aggressive cattle to the competition, while the local community sent a cattle calf who was still breastfeeding to the competition. In the competition, the cattle calf who was still breastfeeding thought the large and aggressive cattle was the mother. So the calf immediately ran towards the large and aggressive cattle to find milk until he tore apart the big cattle's stomach. The victory inspired the local people to use the name Minangkabau, which comes from the phrase "Manang kabau" (winning cattle). The story of the Tambo is also found in the Hikayat Raja-raja Pasai which also mentions that the victory made the country that was previously named Pariangan changed to the name Minangkabau. Furthermore, the use of the name Minangkabau is also used to refer to a nagari (village), namely the Nagari Minangkabau, which is located in Sungayang District, Tanah Datar Regency.

In the historical record of the Majapahit Empire, Nagarakretagama which dated from 1365, also mentioned the name Minangkabwa as one of the Malay countries that has been conquered by the Majapahit. Likewise in the Ming Chronicles from 1405, there was the royal name of Mi-nang-ge-bu of the six kingdoms who sent messengers facing Yongle Emperor in Nanjing. On the other hand, the name Minang (Minanga kingdom) itself has also been mentioned in the Kedukan Bukit inscription dated from 682 which is written in Sanskrit. In the inscription, it was stated that the founder of the Srivijaya Empire named Dapunta Hyang departed from a place called Minānga. Some experts who refer to the source of the inscription suspects that the 4th line words (... minānga) and the 5th line words (tāmvan ...) are actually incorporated, so that they become mināngatāmvan and are translated as the meeting point of twin rivers. The twin river is supposed to refer to the meeting of two sources of the Kampar River, namely the Kampar Kiri River and the Kampar Kanan River. But this hypothesis is denied by the Dutch indologist Johannes Gijsbertus de Casparis, which proves that tāmvan has nothing to do with "meeting point", because these can also be found in other Srivijaya relics.

From the stories of the tambo passed from generation to generation, the ancestors of the Minangkabau people were the descendants of Iskandar Zulkarnain (Alexander the Great). This tambo story is more or less comparable to the Malay Annals who also tells how the Minangkabau people sent their representatives to ask Sang Sapurba, one of the descendants of Iskandar Zulkarnain, to become their king.

The Minang community is part of the Deutro-Malay community who migrated from Southern China to the island of Sumatra around 2,500–2,000 years ago. It is estimated that this community group entered from the east of the island of Sumatra, along the Kampar River to the highlands called darek which became the home of the Minangkabau people. Some of these darek areas then form a kind of confederation known as luhak, which is then referred to as Luhak Nan Tigo, which consists of Luhak Tanah Data, Luhak Agam, and Luhak Limopuluah Koto. During the era of the Dutch East Indies, the luhak area became a territorial government area called afdeling, headed by a resident who by the Minangkabau community was called the name Tuan Luhak. Initially, The Minangkabau people were included as a sub-group of the Malays, but since the 19th century, the Minangkabau and the Malays began to be seen as distinguished, from the matrilineal culture of the Minangkabau that persisted compared to the patrilineal culture adopted by Malay society in general.

According to the Minangkabau Tambo, in the period between the 1st century to the 16th century, many small kingdoms stood on what is now West Sumatra. These kingdoms included the Kuntu, Kandis, Siguntur, Pasumayan Koto Batu, Batu Patah, Sungai Pagu, Inderapura, Jambu Lipo, Taraguang, Dusun Tuo, Bungo Setangkai, Talu, Kinali, Parit Batu, Pulau Punjung. These kingdoms were short lived, and are usually under the influence of larger kingdoms, such as Malayu and Pagaruyung.

The Malayu Kingdom is estimated to have appeared in the year 645 thought to be located in the upper reaches of the Batang Hari River. Based on the Kedukan Bukit inscription, this kingdom was conquered by the Srivijaya in 682. And then in 1183 it appeared again based on the Grahi inscription in Cambodia, and then the Negarakertagama and Pararaton recorded the existence of the Malay Kingdom which had its capital in Dharmasraya. A military expedition to West Sumatra called the Pamalayu emerged in 1275–1293 under the leadership of Kebo Anabrang of the Singasari Kingdom. After the submission of the kingdom recorded on the Amoghapasa carved on the Padang Roco Inscription, the Pamalayu returned to Java with the daughters of King Dharmasraya, Dara Petak and Dara Jingga. Dara Petak was married to Raden Wijaya, the king of Majapahit, as well as the heir to the Singhasari kingdom, while Dara Jingga was married to Adwayawarman. Jayanagara was born from the marriage of Raden Wijaya and Dara Petak, who would become the second king of Majapahit, while Adityawarman was born from the marriage of Dara Jingga and Adwayawarman; he later became king of the Pagaruyung Kingdom.

Hindu-Buddhist influence in western Sumatra emerged around the 13th century, and began during the Pamalayu expedition by Kertanagara, and later during the reign of Adityawarman and his son Ananggawarman. Adityawarman's kingdom had the strength to dominate the central Sumatra region and its surrounding. This was proven by the title Maharajadiraja which was held by Adityawarman recorded on the back of the Amoghapasa carving, found in the upper reaches of the Batang Hari River (now part of the Dharmasraya Regency). The Batusangkar inscription mentioned Ananggawarman as a yuvaraja performing the Tantris teaching ritual from Buddhism called hevajra which is the ceremony of the transfer of power from Adityawarman to his crown prince, this can be attributed to the Chinese chronicle of 1377 about the San-fo-ts'i messenger to the Emperor of China requesting recognition as ruler of the San-fo-ts'i region. Some inland areas of central Sumatra are still influenced by Buddhism, evident in the Padangroco temple, the Padanglawas temple and Muara Takus temple, the areas that were formerly part of Adityawarman's land. Whereas the recorded devout adherents besides Adityawarman, were Kublai Khan and king Kertanegara of Singhasari.

The spread of Islam after the end of the 14th century had little effect, especially relating to the patrilineal system, and gave a relatively new phenomenon to the people in the interior of Minangkabau. At the beginning of the 16th century, the Suma Oriental, written between 1513 and 1515, recorded from the three Minangkabau kings, only one of whom had been a Muslim convert from 15 years before. The influence of Islam in Pagaruyung developed around the 16th century, namely through travelers and religious teachers who stopped or came from Aceh and Malacca. One of the famous ulama of Aceh, Abd al-Rauf al-Sinkili, was a cleric who was thought to first spread Islam in Pagaruyung. By the 17th century, the Kingdom of Pagaruyung transformed itself into an Islamic sultanate. The first Islamic king in the Minangkabau traditional culture was Sultan Alif.

With the entry of Islam, the customary rules that are contrary to the teachings of Islam began to be replaced with the Islamic-based customary law. There is a famous Minangkabau custom proverb, "Adat basandi syarak, syarak basandi Kitabullah", which means that the Minangkabau adat is based on Islam, while Islam is based on the Qur'an. But in some cases, several systems and methods of adat were still maintained causing the outbreak of civil war known as the Padri War. The war was initially between the ulamas and the Adats, who were the Minangkabau nobility and traditional chiefs; later, the Dutch involved themselves in the war.

Islam also had an influence on Pagaruyung kingdom's government system with the addition of government elements such as Tuan Kadi and several other terms related to Islam. The naming of the Sumpur Kudus District, which contains the words derived from the word Quduus (holy) as the seat of Rajo Ibadat and Limo Kaum which contains the word qaum is an influence from Arabic or Islam. In addition, in the adat, the term Imam, Katik (Khatib), Bila (Bilal), Malin (Mu'alim), which is a substitute for Hindu and Buddhist terms used previously, such as the term Pandito (priest), also appears.

At the beginning of the 17th century, the Pagaruyung Kingdom was forced to recognize the sovereignty of the Aceh Sultanate, and to recognize the designated Aceh governors for the west coast of Sumatra. But around 1665, the Minangkabau people on the west coast rebelled against the Aceh governor. From the letter of the Minangkabau ruler Raja Pagaruyung submitted a request to the Dutch East India Company (VOC), and the VOC at that time took the opportunity to end Aceh's monopoly on gold and pepper. Furthermore, the VOC through its regent in Padang, Jacob Pits whose territory included from Kotawan in the south to Barus in the north sent a letter dated October 9, 1668 addressed to the Ahmadsyah Sultan, Iskandar Zur-Karnain, the Minangkabau ruler who was rich in gold, was told the VOC controlled the west coast area so that the gold trade can be re-flowed through the coast. According to Dutch records, Sultan Ahmadsyah died in 1674 and was replaced by his son Sultan Indermasyah. When the VOC succeeded in expelling the Aceh Sultanate from the coast of West Sumatra in 1666, Aceh's influence weakened on Pagaruyung. The relationship between the outer regions and the coast with the Kingdom of Pagaruyung becomes closer. At the time Pagaruyung was one of the trading centers on the island of Sumatra, due to its production of gold, it attracted the attention of the Dutch and the British to establish relations with Pagaruyung. It is recorded that in 1684, a Portuguese explorer named Tomas Dias paid a visit to Pagaruyung at the behest of the Dutch governor general in Malacca.

Around 1750 the Pagaruyung kingdom began to dislike the presence of the VOC in Padang and once tried to persuade the British who were in Bengkulu to expel the Dutch from the region which the British did not respond to. But in 1781, the British managed to control Padang for a short period of time, and messengers from Pagaruyung congratulated the success of the British in expelling the Dutch from Padang. Minangkabau land has long been considered rich in gold, and at that time the power of the Minangkabau king was divided into king Suruaso and the king of Sungai Tarab with the equal power. Previously in 1732, the VOC regent in Padang had noted that there was a queen named Yang Dipertuan Puti Jamilan who had sent spears and swords made from gold, as a sign of her inauguration as the ruler of the land. While the Dutch and British succeeded in reaching the interior of the Minangkabau region, they had never found significant gold reserves in the area.

As a result of the conflict between the British and French in the Napoleonic Wars where the Dutch were on the French side, the British fought the Dutch and again succeeded in taking control of the coast of West Sumatra between 1795 and 1819. The British governor Thomas Stamford Raffles visited Pagaruyung in 1818, when the Padri War began. At that time Raffles discovered that the capital city of the kingdom had been burned because of the war. After the signing of a peace agreement between the British and the Netherlands was signed in 1814, the Dutch re-entered Padang in May 1819. The Dutch reaffirmed their influence on the island of Sumatra and Pagaruyung, with the signing of the Anglo-Dutch Treaty of 1824. The power of the king of Pagaruyung was very weak in the days leading up to the Padri war, although the king was still respected by his subject. The areas on the western coast fell into the influence of Aceh, while Inderapura on the southern coast practically became an independent kingdom although officially still under the rule of the king of Pagaruyung.

In the early 19th century a conflict broke out between the Padri and the Adat. In several negotiations there was no agreement between them. Pagaruyung's kingdom was in turmoil, and the peak of the war was when the Padri under the leadership of Tuanku Pasaman attacked Pagaruyung in 1815. Sultan Arifin Muningsyah was forced to abdicate and escape from the royal capital to Lubuk Jambi. Under pressure by the Padri, the Pagaruyung royal family requested assistance from the Dutch, and before that they had conducted diplomacy with the British when Raffles visited Pagaruyung and promised them assistance. On February 10, 1821, Sultan Tangkal Alam Bagagarsyah, the nephew of Sultan Arifin Muningsyah, in Padang along with 19 other traditional leaders signed an agreement with the Dutch to cooperate in fighting the Padri, even though he was considered not entitled to make an agreement on behalf of the kingdom of Pagaruyung. As a result of this agreement, the Netherlands considered it a sign of surrender of the kingdom of Pagaruyung to the Dutch government. After the Dutch captured Pagaruyung from the Padri, in 1824 at the request of Lieutenant Colonel Raaff, Sultan Arifin Muningsyah returned to Pagaruyung, but in 1825, Sultan Arifin Muningsyah, the last king in Minangkabau, died and was later buried in Pagaruyung. Sultan Tangkal Alam Bagagarsyah on the other hand wanted to be recognized as the king of Pagaruyung, but the Dutch East Indies government had limited his authority and only appointed him the Regent of Tanah Datar. Because of the policy it encouraged Sultan Tangkal Alam Bagagarsyah to start thinking about expelling the Dutch from the region.

After emerging victorious from the Diponegoro War in Java, the Dutch then tried to conquer the Padri with shipments of soldiers from Java, Madura, Celebes and the Moluccas. But the Dutch colonial ambitions caused the Adat and the Padri to forget their differences in secret to drive the Dutch away. On 2 May 1833 Sultan Tangkal Alam Bagagarsyah was captured by Lieutenant Colonel Elout in Batusangkar on charges of treason. He was exiled to Batavia (present-day Jakarta) until his death, and was buried in the Mangga Dua cemetery. After the fall, the influence and prestige of the kingdom of Pagaruyung remained high, especially among Minangkabau people who were overseas. One of Pagaruyung's royal heirs was invited to become a ruler in Kuantan, Malaysia. Likewise when Raffles was still on duty in the Malay Peninsula, he met Pagaruyung's relatives who were in Negeri Sembilan, and Raffles intended to appoint Yang Dipertuan Ali Alamsyah who he considered to be the direct descendant of the Minangkabau kings as a king under British protection. After the end of the Padri War, Tuan Gadang of Batipuh asked the Dutch East Indies government to give a higher position than just as the Tanah Datar Regent which he held after replacing Sultan Tangkal Alam Bagagarsyah, but this request was rejected by the Dutch, this later included one of the drivers of the outbreak of the 1841 rebellion in Batipuh in addition to the cultuurstelsel problem.

The name West Sumatra originated in the Vereenigde Oostindische Compagnie (VOC) era, where the designation of the area for the west coast of Sumatra was Hoofdcomptoir van Sumatra's Westkust. Then with the strengthening of the political and economic influence of the VOC, until the 18th century this administrative region included the west coast of Sumatra from Barus to Inderapura. Along with the fall of the Kingdom of Pagaruyung, and the involvement of the Dutch in the Padri War, the Dutch East Indies government began to make the interior of Minangkabau a part of Pax Nederlandica, an area under Dutch supervision, and the Minangkabau region was divided into the Residentie Padangsche Benedenlanden and the Residentie Padangsche Bovenlanden. Furthermore, in the development of the colonial administration of the Dutch East Indies, this area was incorporated in the Gouvernement Sumatra's Westkust, including the Residentie Bengkulu region which had just been surrendered by the British to the Dutch. Then expanded again by including Tapanuli and Singkil. But in 1905, the status of Tapanuli was upgraded to Residentie Tapanuli, while the Singkil area was given to Residentie Atjeh. Then in 1914, Gouvernement Sumatra's Westkust, was demoted to Residentie Sumatra's Westkust, and added the Mentawai Islands region in the Indian Ocean into Residentie Sumatra's Westkust, and in 1935 the Kerinci region was also incorporated into Residentie Sumatra's Westkust. After the breakdown of the Gouvernement Sumatra's Oostkust, the Rokan Hulu and Kuantan Singingi regions were given to Residentie Riouw, and Residentie Djambi was also formed in almost the same period.

During the Japanese occupation, Residentie Sumatra's Westkust changed its name to Sumatora Nishi Kaigan Shu. On the basis of military geo-strategy, the Kampar area was separated from Sumatora Nishi Kaigan Shu and incorporated into the territory of Rhio Shu.

At the beginning of Indonesian independence in 1945, the West Sumatra region was incorporated in the Sumatra province based in Bukittinggi. Four years later, Sumatra Province was divided into three provinces: North Sumatra, Central Sumatra, and South Sumatra. West Sumatra, Riau and Jambi were part of the residency within the province of Central Sumatra. During the PRRI rebellion, based on emergency law number 19 of 1957, Central Sumatra Province was further divided into three provinces: West Sumatra Province, Riau Province, and Jambi Province. The Kerinci region which was previously incorporated in the South Sumatra Regency of Kerinci, was incorporated into Jambi Province as a separate regency. Likewise, the Kampar, Rokan Hulu and Kuantan Singingi areas are designated as part of Riau Province.

Communism in Sumatra has historically had an influence in the politics and society of Sumatra. Padang, Pariaman, Silungkang, Sawah Lunto, Alahan Panjang and Suliki of West Sumatra have been cited as areas which were particularly active in communism. During the PRRI rebellion, the insurgents arrested leftist activists and placed them in detention camps in West Sumatra. PKI cadres were detained at Situjuh and Suliki, while followers of the national communist Murba Party and other groups were detained at the Muara Labuh camp. Incidentally, Hadji Abdullah Ahmad, a noted anti-communist and religious leader was from the Minangkabau Highlands, where communism was active. Numerous examples of anti-communist resentment also occurred, for instance during the Indonesian killings of 1965–1966, PKI-organised squatters' movements and campaigns against foreign businesses in Sumatra's plantations provoked quick reprisals against Communists. Repression against alleged PKI members and sympathizers continued for several years. As late as 1976 mass lay-offs of former members of the communist plantation workers' union Sarbupri members took place in Sumatra, actions motivated by the communist past of these individuals.

West Sumatra lies in the middle of the western coast of Sumatra, and has an area of 42,119.54 km. Geographic features include plains, mountainous volcanic highlands formed by the Barisan mountain range that runs from north-west to south-east, and an offshore island archipelago called the Mentawai Islands. The West Sumatran coastline faces the Indian Ocean and stretches 375 km from North Sumatra province in the north-west to Bengkulu in the south-east. The lakes of West Sumatra include: Maninjau (99.5 km), Singkarak (130.1 km), Diatas (31.5 km), Dibawah (14.0 km) and Talang (5.0 km). Most of the rivers in West Sumatra flow into the Strait of Malacca, include: Batanghari, Kampar, Ombilin and Sinamar, and others flow into the Indian Ocean, include: Kuranji, Anai and Arau. The mountains and volcanoes of West Sumatra include: Kerinci (3,805 m), Talakmau (2,912 m), Marapi (2,891 m), Singgalang (2,877 m), Talang (2,572 m), Tandikat (2,438 m) and Sago (2,271 m).

West Sumatra is one of the earthquake-prone areas in Indonesia, due to its location in the tectonic slab located between the confluence of two major continental plates (the Eurasian Plate and Indo-Australian Plate) and Great Sumatran fault, plus the activity of the active volcanoes. Large earthquakes that occurred recently in West Sumatra earthquake were the 2009 Sumatra earthquake and the 2010 Mentawai earthquake and tsunami. The area was also affected by the 2004 Indian Ocean Tsunami.

This region has a tropical monsoon climate, similar to most other Indonesian provinces. Throughout the year the province is only affected by two seasons, namely the rainy season and the dry season. The air temperature varies from 24.7 to 32.9 degrees Celsius with air humidity levels ranging from 82% to 88%. The relative rainy season falls from October to April. Variation in rainfall ranges from 2,100 mm to 3,264 mm. The month December is the month with the most rainfall. While the dry season usually starts in June to September.

The season in West Sumatra is similar to other regions in Indonesia, only known for two seasons, namely the dry season and the rainy season. From June to September wind flows from Australia and do not contain much water vapor, resulting in a dry season. Conversely in December to March many wind currents contain water vapor from Asia and the Pacific Ocean during the rainy season. Such conditions occur every half-year after passing the transition period in between April – May and October – November.

The city of Padang is one of Indonesia's wettest cities, with frequent rainfall throughout the course of the year.

As in most other province of Indonesia, West Sumatra has a tropical rainforest climate (Köppen climate classification Af) bordering on a tropical monsoon climate. The climate is very much dictated by the surrounding sea and the prevailing wind system. It has high average temperature and high average rainfall.

The province includes large areas of dense tropical forest, which is home to a host of species including: Rafflesia arnoldii (world's largest flower), Sumatran tiger, siamang, Malayan tapir, Sumatran serow, rusa deer, Malayan sun bear, Bornean clouded leopard, and many birds and butterflies.

The province includes two national parks: Siberut National Park and Kerinci Seblat National Park, as well as a number of nature reserves: Rimbo Panti Nature Reserve, Batang Palupuh Nature Reserve, Lembah Anai Nature Reserve, Lembah Harau Nature Reserve, Bung Hatta Grand Forest Park, and Beringin Sakti Nature Reserve.

The Province of West Sumatra is led by a governor who is elected directly with his representative for a 5-year term. In addition to being a regional government, the Governor also acts as a representative or extension of the central government in the province, whose authority is regulated in Law No. 32 of 2004 and Government Regulation number 19 of 2010.

While the relationship between the provincial government and the regency and city governments is not a sub-ordinate, each of these regional governments governs and manages government affairs according to the principle of autonomy and co-administration.

Until 1979, the smallest administrative unit in West Sumatra was called a nagari, which had existed before Indonesian independence. With the enactment of Law No. 5 of 1979 concerning village governance, the status of nagari was eliminated and replaced with villages, and several jorong statuses were upgraded to villages. The position of nagari guardians was also removed and government administration was carried out by village heads. But since the onset of government reform and regional autonomy, since 2001, the term nagari has been used again in this province.

The political culture that lived in the West Sumatra village government since the policy of uniformity (Law No.5 of 1979) was applied to the parochial political culture. this condition is seen through the power system, the ruling system, the terms of the ruler, and the role of the ruler in the village government.

The kinship system in developing participant political culture began to shift, in terms of the level of sensitivity, the form of tolerance in kinship, and the role of seniority in kinship. This means that the lack of togetherness in the kinship power system.

Nagari government is an autonomous government structure, has a clear territory and adheres to adat as a regulator of the life of its members. the regency replaced the term village government that was used previously. Whereas for the nagari in the city government system still as a traditional institution, it has not become part of the regional government structure.

Opportunities that occur in village government are the emergence of individualistic economic growth. This condition is a result of dependence on the central government, resulting in lack of independence. This condition can weaken the resilience of the area of the economy itself. However, now the villages of West Sumatra have tried to build efforts to facilitate the political policies of the village government or since exchanging back into nagari, namely changing the structure and process between village government structures made under Law No. 5 of 1979.

Nagari was initially led jointly by the princes or datuk in the nagari, then during the Dutch East Indies government one of the princes was chosen to become the guardian of the Nagari. Then in running the government, the nagari guardians are assisted by a number of jorong or jorong guardians, but now assisted by the nagari secretary and civil servants depending on the needs of each nagari. This nagari guardian was chosen by the anak nagari (nagari residents) democratically in direct elections for 6 years in office.

West Sumatra Province is subdivided into twelve regencies and seven autonomous cities, which lie outside any regency. The regencies and cities are listed below with their areas and their populations at the 2010 Census and 2020 Census, together with the official estimates as at mid 2023.