sentences:  He did briefly recover the electorate during the period 1554–1556, but his involvement in political intrigues angered the Emperor Maximilian II.The Emperor finally imposed the "Reichsacht" (Imperial ban) on him, which made him the object of a "Reichsexekution" (Imperial police action) in which Johann Wilhelm participated.After a siege of his castle in Gotha, Johann Friedrich was finally defeated in 1566 and spent the rest of his life as an Imperial prisoner.