CELEBRATE | International Women’s Day Marks 100th Anniversary

The first person to pack a dress for Congress, Rankin served one term, as a Republican rep from Montana, then returned to the House in 1940. She was the lone vote against the U.S. declaring war on Japan.

After her husband was assassinated, Sri Lanka's Bandaranaike ran for his spot and became the world's first elected female prime minister. She led the country's transition to a republic, in 1972, and its name change from Ceylon.

The Seagull isn't just one of Russia's most famous plays; it was also the code name for one of the country's most notable cosmonauts. The first woman in space, Tereshkova orbited Earth for 71 hours aboard Vostok 6.

Woman numero uno to head a Fortune 500 company, the Washington Post publisher's better-known accolades came for her controversial decisions to publish the Pentagon Papers and the Watergate break-in coverage.

Nominated to the Supreme Court by President Reagan in 1981, O'Connor's moderate approach over 24 years played a pivotal role in decisions on abortion, affirmative action, and antiterrorist detention policies.

It was 1970 before the U.S. Army promoted its first female one-star general -- and it took 38 more years before a woman, Dunwoody, would reach the highest rank as a four-star. She now heads one of the military's largest commands.

A version of this article appears in the March 2011 issue of Fast Company.