Catherine II, born a minor German princess, became Russia’s longest-ruling female leader through a coup that deposed her husband, Peter III. An 'Enlightened Despot,' she corresponded with thinkers like Voltaire and Diderot, attempting to modernize Russian law and education. Under her reign, the Russian Empire expanded significantly, gaining territory in the south through wars with the Ottoman Empire and in the west through the partitions of Poland. She established the Hermitage Museum and the first state-funded higher education institution for women in Europe (the Smolny Institute). While she failed to abolish serfdom due to the resistance of the nobility, she oversaw a period of immense cultural and political growth known as the Catherinian Era. Catherine transformed Russia into a dominant European power, balancing traditional autocracy with the intellectual currents of the Enlightenment, making her one of history's most effective and powerful monarchs.