Short answers, pulled from the story.
Catherine the Great was born Princess Sophie Auguste Friederike von Anhalt-Zerbst-Dornburg on the 2nd of May 1729 in Stettin, Prussian Pomerania. She became Empress of Russia in 1762 through a coup d'etat against her husband, Peter III, and reigned until 1796.
Peter III died at Ropsha on the 17th of July 1762, eight days after the coup that removed him. He died possibly at the hands of Alexei Orlov, and the official cause after an autopsy was a severe attack of haemorrhoidal colic and an apoplexy stroke, though whether he was assassinated remains unknown.
Catherine the Great extended Russia's borders by some 200,000 square miles, absorbing New Russia, Crimea, the North Caucasus, right-bank Ukraine, Belarus, Lithuania, and Courland. She annexed Crimea in 1783 and founded new southern cities including Odessa, Nikolayev, Kherson, and Yekaterinoslav.
Catherine the Great placed her former lover Stanislaus Augustus Poniatowski on the Polish throne in 1764 and took a leading role in partitioning the Polish-Lithuanian Commonwealth. On the 24th of October 1795 the three partitioning powers signed a treaty erasing any independent Polish state from the map.
A census taken between 1754 and 1762 recorded that Catherine the Great owned 500,000 serfs, with a further 2.8 million belonging to the Russian state. Under her rule a landowner could sentence serfs to hard labour in Siberia, and discontent helped fuel Pugachev's Rebellion of 1774.
Catherine the Great corresponded with Voltaire for fifteen years, worked with Diderot and other French encyclopedists, and summoned a 652-member Grand Commission in 1766 to write Enlightenment principles into law. She founded the Smolny Institute in 1764, the first state-financed higher education institution for women in Europe.
Catherine the Great had herself inoculated against smallpox by the English doctor Thomas Dimsdale and promoted inoculation across her empire. By 1800 roughly 2 million inoculations had been administered in the Russian Empire, almost 6 percent of the population, and she opened the Moscow Foundling Home in 1764 and Paul's Hospital in 1763.