h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

you might want to mention in passing the Pig War of 1858? When the border between what became British Columbia and what became Washington state was fixed, nobody thought about the cluster of islands off the Pacific coast straggling the border - these were uncertain territory. Britain and the USA clashed over a dispute between one settler on the islands claiming Canadian nationality and another claiming US nationality - apparently American pigs were snuffling up and wrecking Canadian crops. This escalated and troops of both sides were called to the disputed island. fortunately the relatively junior British and US officers involved had the common sense to realise it was crazy to start a war between two great powers - over a pig. requests went to Washington and London for guidance and eventually the Germans were asked to be neutral adjudicators - they found in favour of the USA. This was in 1858, I think.

You are close, I think: Researcher Florida Sailor says it was 1859 in his Guide Entry on the Pig War: A87885030