When Hanover was The Kingdom of Hanover and a nation it existed from October 1814 until it's annexation
into the German Empire in 1866. Although as a nation it does not exist anymore, it is one of 3 German "Herrschafts" similar to a British Dominion in that it is partially self-governing. It is a major part of Germany's economic and military mite. Hanover was, throughout it's time as a Kingdom, in a union under the British and maintains the best relations with the British of any part of Germany. Hanover has, in the last 25 years, had 3 referendums on independence from Germany. None have passed.