United States

• Washington Territory

 United Kingdom

• Colony of Vancouver Island

Commanders and leaders Strength 461 combatants, 14 cannons 2,140 combatants; 5 warships mounting 70 cannons

The Pig War was a confrontation in 1859 between the United States and the United Kingdom over the British–U.S. border in the San Juan Islands, between Vancouver Island (present-day Canada) and the Washington Territory (present-day State of Washington). The Pig War, so called because it was triggered by the shooting of a pig, is also called the Pig Episode, the Pig and Potato War, the San Juan Boundary Dispute, and the Northwestern Boundary Dispute. Despite being referred to as a "war", there were no human casualties on either side.

The Oregon Treaty of June 15, 1846, resolved the Oregon boundary dispute by dividing the Oregon Country/Columbia District between the United States and Britain (future Canada) "along the 49th parallel of north latitude to the middle of the channel which separates the continent from off-shore Vancouver Island, and thence southerly through the middle of the said channel, and of the Strait of Juan de Fuca, to the Pacific Ocean."

However, two straits could be called the middle of the channel: Haro Strait, along the west side of the off-shore San Juan Islands; and Rosario Strait, along the east side.

In 1846, there was still some uncertainty about the region's physical geography. The most commonly available maps were those of Royal Navy Captain George Vancouver (1757-1798), published in 1798, and of the United States Navy's Charles Wilkes (1798-1877), published in 1845. In both cases, the maps are unclear in the vicinity of the southeastern coast of Vancouver Island and the Gulf Islands. As a result, Haro Strait is not fully clear either.

In 1856, the U.S. and Britain set up a Boundary Commission to resolve several issues regarding the international boundary, including the water boundary from the Strait of Georgia to the Strait of Juan de Fuca. The British appointed James Charles Prevost (1810-1891), as First Commissioner, George Henry Richards (1820-1896) as Second Commissioner, and William A. G. Young (1827-1885) as Secretary. The U.S. appointed Archibald Campbell First Commissioner, John Parke (1827-1900), Second Commissioner, and William J. Warren Secretary. On June 27, 1857, the American and British commissioners met for the first time on board the British Royal Navy warship HMS Satellite, anchored in Esquimalt Harbour. The two sides met several more times in 1857 in Esquimalt Harbour and Nanaimo Harbour, and corresponded by letter between meetings. The water boundary was discussed from October to December. From the start, Prevost maintained that Rosario Strait was required by the treaty's wording and was intended by the treaty framers, while Campbell had the same opinion for Haro Strait.

Prevost held that the channel specified in the treaty must have three essential qualities:

• it must separate the continent from Vancouver Island
• it must carry the boundary in a southerly direction
• it must be navigable

Only Rosario fulfilled these requirements, he wrote. Campbell countered that the expression "southerly", in the treaty, was to be understood in a general sense, that Rosario Strait did not separate the continent from Vancouver Island, but the San Juan Islands from Lummi Island, Cypress Island, Fidalgo Island, and others, and that navigability was not germane to the issue, but even if it was, Haro Strait was the wider and more direct passage. Finally, he challenged Prevost to produce any evidence showing that the treaty framers had intended Rosario Strait. Prevost responded to the challenge by referring to American maps showing the boundary running through Rosario Strait, including one by John C. Frémont, produced for and published by the US government, and another by John B. Preston, Surveyor General of Oregon in 1852. To the other points, Prevost repeated his statements about Rosario Strait's navigability—the channels between Lummi, Cypress, and Fidalgo islands not being navigable—and that a line through Rosario would be southerly. At the same time, one through Haro would have to be drawn westerly. The two continued to discuss the issue into December 1857, until it was clear what each side's argument was and that neither would be convinced of the other. Prevost made a final offer at the sixth meeting, on December 3. He suggested a compromise line through San Juan Channel, which would give the US all the main islands except San Juan Island. This offer was rejected and the commission adjourned, agreeing to report back to their respective governments. Thus ambiguity over the water boundary remained.

Because of this ambiguity, both the United States and Britain claimed sovereignty over the San Juan Islands. During this period of disputed sovereignty, Britain's Hudson's Bay Company established operations on San Juan and turned the island into a sheep ranch. Meanwhile, by mid-1859, twenty-five to twenty-nine American settlers had arrived.

San Juan Island held significance not for its size, but as a military strategic point. While the British held Fort Victoria on Vancouver Island to the west, overlooking the Strait of Juan de Fuca, the entry point to Haro Strait, leading to the Strait of Georgia, the nation that held the San Juan Islands would be able to dominate all the straits connecting the Strait of Juan de Fuca with the Strait of Georgia.

Former Union Army General-in-Chief (1861-1862), George B. McClellan (1826-1885), and George Pickett (1825-1875)’s classmate at the United States Military Academy at West Point, New York and lifelong friend, although military opponent, claimed that General William S. Harney (1800-1889), and Pickett conspired with a cabal, to start a war with Britain (United Kingdom), creating a common enemy, to head off a north–south confrontation. However, General Granville O. Haller (1819-1897), disputed General McClellan's later theory. He said they had wanted to start a war, but with hope of distracting the North so that the South could secede from the federal Union. The theories are given credence when it is noted that later Major General Silas Casey (1807-1882), then a lieutenant colonel and deputy commander of the 9th Infantry Regiment, was reduced to a support role for lower ranked Captain George Pickett who was given independent jurisdiction over a vast area by General William Harney, then a brevet major, and was also passed over by Harney in favor of Captain Pickett when given this choice command.

On the other hand, it can be said that Lieutenant Colonel Casey had not been reduced, for he was given command over the U.S.S. Massachusetts and Major Haller to protect and supervise the waters of the Puget Sound. Based on his military experience, he was given discretion to deviate from his orders.

On June 15, 1859, exactly 13 years after the adoption of the Oregon Treaty, the ambiguity led to direct conflict. Lyman Cutlar, an American farmer who had moved onto San Juan Island claiming rights to live there under the Donation Land Claim Act, passed nine years earlier by the U.S. Congress in 1850, found a pig rooting in his garden and eating his tubers. This was not the first occurrence and as a result Cutlar tired of the intrusion, shot and killed the pig. It turned out that the pig was owned by an Irishman, Charles Griffin, who was employed by the Hudson's Bay Company to run their sheep ranch on the island. He also owned several pigs that he allowed to roam freely. The two had lived in peace until this incident. Cutlar offered $10 dollars (equivalent to $340 in 2023) to Griffin to compensate for the pig, but Griffin was unsatisfied with this offer and demanded $100 dollars (equivalent to $3,400 in 2023). Following this reply, Cutlar believed he should not have to pay for the pig because the pig had been trespassing on his land. One likely apocryphal account has Cutlar saying to Griffin, "It was eating my potatoes"; and Griffin replying, "It is up to you to keep your potatoes out of my pig." When British authorities threatened to arrest Cutlar, nearby American settlers called for military protection in the Washington Territory from the United States Army.

Brigadier General William S. Harney (1800-1889), then commanding the military Department of Oregon on the West Coast, initially dispatched then Captain George Pickett (1825-1875), and 66 American soldiers of the 9th Infantry Regiment under Pickett's command, to the off-shore San Juan Island with orders to prevent the British from landing; the regiment sailed aboard the wooden-hulled steamer warship USS Massachusetts. Concerned that a squatter population of Americans would begin to occupy San Juan Island if the Americans were not kept in check, the British on Vancouver Island then sent three Royal Navy warships under the command of Captain Geoffrey Hornby (1825-1895), to counter the perceived Americans' infringement. Captain Pickett was quoted as saying defiantly, "We'll make a Bunker Hill of it," placing him later in the national limelight reported in the press. Pickett sited his company and battery near the Hudson's Bay Company's Belle Vue sheep farm near today's Cattle Point Light, and directly under the guns of H.M.S. Satellite, a British warship. When this tactical error was pointed out, Capt. Pickett moved his battery of cannon a few miles north to high ground overlooking both Griffin Bay and the entrance waterway of the Strait of Juan de Fuca to the Puget Sound (and important American new seaport at Seattle in the former Oregon Territory (1848-1853/1859), later split off in the new Washington Territory, 1853-1889), and commenced to build a redoubt for his cannon.

Captain Pickett established the American military camp near the south end of San Juan Island, today one of two historical sites on the island, the other being the British camp, defended by the Royal Marines on the opposite north end of the island. The U.S. camp redoubt was built under the supervision of new United States Military Academy at West Point, New York graduate, then 2nd Lieutenant Henry Martyn Robert (1837-1923); Robert went on to become a general in the Army of the Potomac of the Union Army during the subsequent American Civil War (1861-1865), and author of Robert's Rules of Order, acclaimed reference manual on democratic parliamentary procedure. Robert's Redoubt of 1859 on the island is considered the best-preserved fortification of its kind now in the United States. (To the east is Jackle's Lagoon, named for George Jackle, a soldier stationed at the American camp.)

The situation continued to escalate. By August 10, 1859, the enlarged defending detachment of now 461 Americans with 14 cannons under Colonel Silas Casey (1807-1882), were opposed by now also reinforced flotilla of five British Royal Navy warships mounting 70 guns and carrying 2,140 men.

The governor of the off-shore Colony of Vancouver Island, James Douglas (1803-1877), had ordered Captain Hornby to dislodge the American troops, avoiding armed conflict if possible. At the time, the additional reinforcements sent by the American General William Harney had not yet arrived, and the island was occupied by only Capt. Pickett's small detachment of 66 men. Hornby refused to take any action until British Rear Admiral Robert L. Baynes (1796-1869), who was in command of the British Royal Navy in the Pacific, would arrive himself and issue commands. When Admiral Baynes finally came later and took stock of the situation, he told Governor Douglas that he would not escalate the conflict into a war between two great nations "over a squabble about a pig".

When news about the developing escalating crisis reached the far-away capitals of London and Washington, D.C., officials from both nations were shocked at the potential conflict and took action to calm the potentially explosive international incident.

In September, the 15th U.S. President James Buchanan (1791-1868, served 1857-1861), sent the U.S. Army's General-in-Chief Winfield Scott (1786-1866), to negotiate with Governor Douglas and resolve the growing crisis and prevent it from spinning out of control. This was in the best interest of the United States, as sectionalist tensions within the American nation itself were rapidly increasing, soon to culminate in the coming bloody American Civil War of 1861-1865. General Scott had calmed two other earlier border crises between the two nations two decades before in the late 1830s. He arrived in the San Juans in October and began negotiations with Governor Douglas on Vancouver Island.

As a result of the negotiations, both sides agreed to retain joint military occupation of the island until a final negotiated diplomatic settlement could be reached, reducing their presence to a token force of no more than 100 men. The British camp was established on the north end of San Juan Island along the shoreline, for ease of resupply and access; and the American camp was created on the south end on a high, windswept meadow, suitable for artillery barrages against passing shipping in the strait. Today the Union Jack flag still flies above the former British Royal Marines camp site, being raised and lowered daily by American National Park Service rangers, making it one of the few places without diplomatic status where U.S. federal government employees regularly hoist the flag of another country, though this is only for commemorative historical and nostalgic purposes.

During the following years of joint military occupation, the small British and American units on San Juan Island had an amicable mutual social life, visiting one another's camps to celebrate their respective national holidays and holding various athletic competitions. N.P.S. park rangers tell visitors the biggest threat to peace on the island during these years of the 1850s and 1860s was "the large amounts of alcohol available".

This state of affairs continued for the next 12 years. The dispute was peacefully resolved after the initial skirmish of more than a decade of confrontation and military bluster, during which time local British mainland authorities lobbied London to seize back the off-shore islands of the Puget Sound region while the Americans were busy elsewhere with the their own Civil War. In 1866, the Colony of Vancouver Island was merged with the short-lived Colony of British Columbia (1858-1866) on the mainland of western North America to form a second enlarged Colony of British Columbia of 1866-1871.

In 1871, the enlarged colony on the West Coast joined the newly-formed confederation of 1867 further east on the continent of the new Dominion of Canada. That year, the United Kingdom and the United States also signed the Treaty of Washington of 1871, which dealt with various remaining minor differences between the two nations, including border issues involving the newly formed self-governing dominion of the British Empire. Among the results of the treaty was the decision to resolve the San Juan Island dispute by international arbitration, under the good offices of mediation offered by the newly-crowned German Emperor (Kaiser) Wilhelm I (1797-1888, reigned as King of Prussia since 1861, then as Emperor 1871-1888), chosen to act as arbitrator, meaning that the recently unified German Empire of 1871-1918 (in Germany) would decide if the British or the Americans would officially own the San Juan Islands off the west coast of North America. Presenting for the United States in the subsequent San Juan arbitration case was the prominent American historian and diplomat (minister / ambassador) and notable former U.S. Secretary of the Navy, of George Bancroft (1800-1891), who displayed great versatility and skill and won the case. German Kaiser Wilhelm I referred the issue to a three-man arbitration commission which met in Geneva, of neutral Switzerland for nearly a year. Finally on October 21, 1872, the commission decided in favor of the United States' offer. The arbitrators chose the American-preferred marine boundary via the waterway of the Haro Strait, to the west of the islands, over the British preference for using the Rosario Strait which lay to their east to demarcate the border extension.

On November 25, 1872, the British withdrew their Royal Marines from the British camp. The Americans followed by July 1874.

The Pig War is commemorated in San Juan Island National Historical Park.

• Second Lieutenant Henry Martyn Robert (1837-1923), of South Carolina / Ohio, who later published the first edition of his Robert's Rules of Order in 1876 on democratic parliamentary procedure, and later became a general in the federal Army of the Potomac of the Union Army during the following Civil War was stationed on the island for much of the period.
• Captain George Pickett (1825-1875), of Virginia, and later a general in the Confederate States Army of the infamous Pickett's Charge fame at the pivotal July 1863 Battle of Gettysburg at Gettysburg, Pennsylvania in the following American Civil War (1861-1865), was in charge of the initial American small landing force on San Juan.
• Captain Geoffrey Hornby (1825-1895), commander of the initial British naval force flotilla deployed, was later promoted to Admiral of the Fleet, the highest rank in the Royal Navy, and earned a reputation as a pre-eminent tactician and fleet commander in the 19th century.

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• The Pig War - OverSimplified on YouTube
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