The Catholic Archdiocese of St. Louis said it extended "prayerful condolences" to Schlafly's family, saying that throughout her life she "displayed an ardent commitment to the teachings and defense of the Catholic faith and for which the Church is grateful."
"We pray for repose of the soul of Mrs. Schlafly and for peace and consolation for her family during this difficult time," the archdiocese said Sept. 7.
Schlafly was born in St. Louis on Aug. 15, 1924. She paid her way through college during World War II by working in an ordinance plant and test-firing machine guns, the Washington Post reports. After earning a master's degree in political science from Radcliffe College in 1945, she worked at the Washington, D.C. organization that would become the American Enterprise Institute, then worked in St. Louis on a congressman's reelection campaign and as a research director for local banks.
She married Fred Schlafly, a wealthy lawyer, in 1949 and became a volunteer and a political activist in the Republican Party. She is remembered for her role in ensuring that the Republican Party remained conservative on social issues during the 1960s and 70s.
Among her positions was researcher for U.S. Sen. Joseph McCarthy of Wisconsin, the anti-communist crusader. She authored or edited 20 books on topics like 1964 Republican presidential candidate Barry Goldwater, national defense, and communism. She also attempted several runs for Congress.
Schlafly rose to prominence through her successful mobilization of opposition to the proposed Equal Rights Amendment to the U.S. Constitution, which appeared likely to be ratified in early 1972.