Alexander I was the Emperor of Russia from 1801 to 1825, known for his role in the Napoleonic Wars and his contributions to the creation of the Concert of Europe. His reign saw significant political and social reforms in Russia, as well as a shift towards conservative ideals after initially supporting liberal ideas. He played a crucial part in establishing a balance of power in Europe post-Napoleon, which aligned with the principles of conservatism that sought to maintain the established order.