During the early 19th century, European leaders met for the Congress of Vienna, which was held to create peace across the continent. Why did this plan fail? Select ALL that apply. A) Language barriers made communication impossible, leading to numerous civil wars created by the Congress within the empires.

B) Not only did most ethnic groups believe in nationalism, but they also did not cooperate with members of their own ethnicity.

C) The Congress purposefully grouped countries together that they knew would fail because they wanted to see Europe fail.

D) The area was so large that it had too many religions and ethnicities to be successful under one leader, who was not democratically elected.