Peter the Great of Russia was a tsar who ruled from 1682 until his death in 1725. He is known for modernizing Russia and transforming it into a major European power. Peter implemented reforms in the military, government, and culture, introducing Western technologies and ideas to Russian society. One of his significant achievements was the founding of Saint Petersburg, which became the new capital of Russia in 1712. Peter the Great also established the Russian Navy and expanded the country's territory through various military campaigns, notably against Sweden during the Great Northern War.