The island of Cabrera, a paradise turned into hell for thousands of Napoleonic soldiers
One of the perhaps most unknown episodes is the fate of the Napoleonic soldiers of General Dupont's regiment in Spain who, after the capitulation in the battle of Bailén in Andalusia, were sent to a desert island in the Balearic Islands, Cabrera. It was in 1809. Thousands of soldiers were left to fend for five years.
There's an interesting account by one of the prisoners in The Young Rifleman's Comrade: A Narrative Military Adventures, Captivity, And Shipwreck by a guy who ended up having enough and enlisting in the KGL. One fellow prisoner apparently resorted to cannibalism.