King Ludwig II mounted the Bavarian throne at 19 at his father's death. His political ambition was to maintain Bavaria as truly sovereign member of the German League of 39 states established after the Vienna Congress. To resist the aggressive Prussian expansion of chancellor Bismarck, he had to side with Habsburg Austria, but was defeated on the battle field and reduced to a Prussian protectorate and forced to join the war against Napoleon III's France, which lead to the Prussian Hohenzollern dynasty being declared German emperors. Ludwig withdrew in wild plans, as an absolutist island realm on Tenerife, and a crushingly expensive fantasy world of staged luxury, championed by castles such as Neuschwanstein and the Wagner theatre, soon running up a huge debt guaranteed by the treasury. The government ended up interning him as mentally incapacitated. His castle lake drowning, aged 40, with his psychiatrist, possibly a suicide related to his gay frustration, remains the stuff of legends.