Peter the Great

Meanwhile, Peter married Eudoxia Lopukhina, who came from a wealthy boyar family.

An excerpt from the article 32 facts about Peter the Great

She married Peter shortly before an attempt on his life, prepared by the Tsar's half-sister Sophia Romanova (Peter threatened her claim to the throne). Three sons were born of the union with Eudoxia: Alexei Petrovich (who was later imprisoned, tortured, and executed in Petropavlovsk on his father's orders), Alexander Petrovich, and Pavel Petrovich. The marriage, however, did not turn out to be a happy one, Peter dismissed his wife and later confined her to the Pokrovsky Monastery in Suzdal.