by Steve

You may recall that Lewis and Clark were sent out to explore the land that the US had acquired in the Louisiana purchase from France. What you might not recall is that this land did not stretch all the way to the Pacific Ocean. This little fact did not stop them from continuing all the way to the ocean, arriving at the mouth of the Columbia River at what is now the border between Oregon and Washington. Of course they claimed the land for the US, despite other nations' claims to it, including Russia, Spain, the British--not to mention the first nations (whom nobody did bother to mention.) Eventually, Spain and Russia dropped their claims, leaving the US and the British claiming to the Oregon territory, which stretched from the southern border of Oregon to well into what is now British Columbia.

The two countries basically agreed to joint occupation of the territory; this lasted from 1818 to 1846, when the border between the 2 nations was set at the 49th parallel.  (Remember "54-40 or Fight!") The British got the whole of Vancouver Island, even though a portion of it extends below the 49th parallel, and the boundary was set at the strait between Vancouver Island and the mainland.

The problem is that there are actually two straits between Vancouver Island and the mainland. The US assumed that the agreement meant the border was the Haro Strait, right beside Vancouver Island. This would make the San Juan Islands part of the US. The British assumed it meant the Rosario Strait, giving the islands to them. Settlers from both countries arrived on the islands, staking their claims. Joint occupation continued, as it had for around 40 years, with both sides getting along with each other. Until the problem in 1859 with the pig.

Here's a summary of the incident, from The Pig War, thanks to the National Park Service:

Both the US and the British began sending troops and cannon to the island, establishing camps, and generally escalating tensions. This despite the fact that the officers from both sides would share whiskey and cigars together, and the soldiers would worship together on Sunday.

The British had the much nicer camp, on a sheltered bay with beautiful views. They spent their time building nice structures and making their camp a good place the live.

The American camp was on the southern end of San Juan Island, on a hill in an exposed place with lots of wind. They spent their time doing military drills.

Fortunately, cooler heads on both sides prevailed, and the stand-off was deescalated a bit. The British commander was not willing to go to war over a pig, and when Washington finally heard of the incident, they dispatched Winfield Scott to contain the situation. He arrived a few months later and proposed a joint military occupation. This lasted until 1872 (over 12 years) until the border dispute was settled by the Kaiser of Germany acting as the arbitrator.

Now the American and English camps are part of a National Monument, and you can visit both and gain a little insight into this strange chapter of our history. Fortunately, no shots were fired by either side in the pig war, other than the shot that killed the pig. The Kaiser ruled in favor of the US, giving the US the San Juan Islands. The British accepted the ruling and immediately withdrew their troops. The islands have been at peace ever since.

I think there's probably a lesson here about letting small stuff escalate, about getting along with your neighbors, and about peacefully resolving disputes.  I'll let readers draw their own conclusions.