During the same period, the Great Idea was established and it was adopted by Otto as a principle of his foreign policy. During the Crimean War (1835-1856), Otto supported liberating movements in Thessaly, Macedonia and Crete, which caused the reaction of England and France. In order for Greece to be forced to become neutral, the two Great Powers blocked the port of Piraeus. Otto was considered to be responsible for the failure of the realization of the Great Idea, while England and France started aspiring to his dethronement.