Wejherowo [vɛi̯xɛˈrɔvɔ] (Kashubian: Wejrowò; formerly German: Neustadt in Westpreußen) is a city in Gdańsk Pomerania, northern Poland, with 48,735 inhabitants (2021). It has been the capital of Wejherowo County in Pomeranian Voivodeship since 1999; previously, it was a city in Gdańsk Voivodeship (1975–1998).

Wejherowo is located in Pomeralia, in the ethnocultural region of Kashubia, approximately 11 km (7 mi) west of the town of Rumia, 32 kilometres (20 miles) east of the town of Lębork and 35 km (22 mi) north-west of the regional metropole of Gdańsk, in the broad glacial valley of the river Rheda at an altitude of 30 metres (98 feet) above sea level.

Wejherowo was founded in 1643 as Wola Wejherowska (literally "Wejher's Wola"), by the voivode of the Malbork Voivodeship, and Polish noble, Jakub Wejher. It was translated in the colloquial German of the time as Weihersfrey or Veyersfrey. According to the founder's will, the dwellers of the new settlement were to possess the same city rights as other towns in the region, hence the place granted Kulm law. The town's privileges, received in 1655, were confirmed by King John II Casimir Vasa of Poland.

Wejher, who survived the Smolensk War, built two churches in the new settlement (The Holy Trinity and Saint Ann). He also brought in Franciscan fathers, built a monastery, and founded a calvary, consisting of 26 chapels, aligned along the border of the town forest, which were built during 1646–55. According to the founder's written statement of 1655, all honorable persons, independent of their nationality, were invited to become citizens of the new settlement if they would pay a citizen fee of ten gulden each.

In the First Partition of Poland in 1772, in which the Kingdom of Prussia annexed most of Pomerelia, the town was incorporated into the Kingdom, and administered within the new province of West Prussia. Its name in German changed from Weyersfrey to Neustadt in Westpreußen, a name which was in use also before. The affix "in West Prussia" was added to the town's name in order to avoid confusion with a number of other towns carrying the same name. Decisive factors which boosted the development of the town in the 19th century were the 1818 establishment of Landkreis Neustadt, an administrative district, and the construction of the Danzig (Gdańsk) – Stettin (Szczecin) railway line, to which Neustadt was connected with a train station in 1870. Neustadt became part of the German Empire in 1871 during the Prussian-led unification of Germany. During the second half of the 19th century, a significant number of Jewish families from the region began migrating to Syracuse, New York, including the renowned Shubert theatrical family. Kashubians and Poles formed 59.3% of population in the district area of the city around this time. The city itself, however, was predominantly German. According to the census of 1910, the city had a population of 9,804, of which 6,970 (71%) were Germans, 2,421 (25%) were Kashubians and 394 (4%) were Poles.

In 1905, Neustadt had a Protestant church, two Catholic churches, a synagogue, a grammar school, a preparatory school for a training college for school teachers, a training college for evangelical school teachers, a mental asylum, a local court, a forest office, cigarette factories, sawmills, a brewery, a cattle trade and wood trade as well as grain trade. During the Partitions, the German authorities led a systemic campaign of Germanization against local the Polish and Kashubian populations, which resisted by organizing the secret patriotic organization Zwiazek Filomatów, distributing the Polish newspaper Gazeta Gdańska, and by establishing various local economic initiatives.

Until 1919, Neustadt belonged to the administrative region of Regierungsbezirk Danzig in the Province of West Prussia in Germany. After World War I and the re-establishment of independent Poland, the town was integrated into the Second Polish Republic. Wejherowo was the capital of Wejherowo County in Pomeranian Voivodeship, becoming a headquarters of state administration responsible for the maritime economy. In 1923–1928, there was a special educational center in Wejherowo, in which about 300 Polish orphans lived and got education after their rescue from war-stricken Siberia with the help of Japan in 1920–1922.

On 9 September 1939, during the invasion of Poland, which marked the beginning of World War II, Wejherowo was captured by the Wehrmacht. Afterwards it was annexed by Nazi Germany and administered as part of Regierungsbezirk Danzig in the newly formed province of Reichsgau Danzig-West Prussia. Most of the town's Jewish community was murdered by the Nazis during the occupation, while many local Poles were also victims of the Nazi extermination policy.

The Einsatzkommando 16 and SS Wachsturmbann "Eimann" entered the county in the first half of September 1939 to commit various crimes against the population. Poles arrested both in Wejherowo and the county were imprisoned in the local prison, and afterwards transported to the nearby village of Piaśnica Wielka, which was the site of a mass murder of about 12,000 Poles in 1939. Among people murdered there were the city's mayor Teodor Roman Bolduan and the wójt of gmina Wejherowo (head of the local gmina) Edward Łakomy. Also Polish students from local high schools were massacred there. Numerous Poles arrested during the Intelligenzaktion in other cities of the region were also briefly held in the local prison before they were murdered in Piaśnica. Among them were local officials, merchants, activists, teachers, priests and civilian defenders of Gdynia. Local teachers were also among Polish teachers and principals murdered in the Mauthausen concentration camp.

In March 1945, Wejherowo was captured by the Soviet Red Army. After the war, in 1945, Wejherowo was reintegrated with Poland. Its first post-war mayor was Bernard Szczęsny, who during the German occupation was part of the Polish resistance movement, was imprisoned in the Stutthof concentration camp and escaped during a death march. Some German perpetrators were not sentenced for their involvement in the crimes committed against Poles in Wejherowo and even retained public offices, including Gustav Bamberger, the town's deputy mayor under German occupation, who participated in the selection of prisoners in the local jail. After the war he served as the deputy mayor of Hanover in West Germany.

Year	Number	Remarks
1789	700
1831	1,690
1845	1,800
1853	2,500
1865	3,200
1875	4,506
1880	4,715
1890	5,546	incl. 2,336 Protestants, 3,039 Catholics and 160 Jews (240 Poles)
1905	8,389	incl. 3,044 Protestants, 5,171 Catholics, 26 other Christians and 148 Jews
1921	8,786
1943	16,490
1948	13,400
1960	24,500
1970	33,800
1980	42,400
1990	46,800
2000	46,200
2006	47,159
2011	49,922
2021	48,735

• Museum of Kashubian and Pomeranian Writing and Music, located in the Przebendowski Palace

The local football club is Gryf Wejherowo. It competes in the lower leagues.

• Kaszubsko-Pomorska Szkoła Wyższa

• 
  Przebendowski Palace
• 
  Aleksander Majkowski Park
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  Wejherowo Calvary
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  Saint Leo church
• 
  Kashubian Philharmonic (Filharmonia Kaszubska)
• 
  Market Square with the Town Hall
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  Powiat (county) office
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  Old townhouses on the Jana Sobieskiego Street
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  Wejherowo railway station
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  Jakub Wejher monument

Wejherowo is twinned with:

Iwano-Frankowsk, Ukraine Postawy, Belarus Tyresö, Sweden

• Official web page of Wejherowo (in English)
• Wejherowo homepage. "Throughout the centuries."
• wejher.com - news, photos, bulletin board (in Polish)
• Wejherowo Land
• Following the trail of manor houses and castles of the Northern Kashubian Region
• Northern Kashubia Heritage