Married to Peter III, for 10 points, identify this ruler, the lover of Grigory Potemkin and suppresser of Pugachev's Rebellion, who after a coup that killed her husband became empress of Russia.
This ruler's actions in the first Partition of Poland sparked the Confederation of Bar, and after defeating the Ottoman Empire in the first Russo-Turkish war Crimea was added to Russia.  This ruler created the League of Armed Neutrality during the American Revolution while collaborating with many Enlightenment figures, notably Voltaire and Denis Diderot.  Married to Peter III, for 10 points, identify this ruler, the lover of Grigory Potemkin and suppresser of Pugachev's Rebellion, who after a coup that killed her husband became empress of Russia.
This ruler's actions in the first Partition of Poland sparked the Confederation of Bar, and after defeating the Ottoman Empire in the first Russo-Turkish war Crimea was added to Russia.  
Catherine II of Russia or Catherine the Great [accept Sophia Augusta Frederica but must have both parts and prompt on partial name]