On May 13, 1846, the United States Congress formally declared war against Mexico, following battles along the disputed U.S.-Mexico border in the preceding weeks; the Mexican-American War would continue until February 1848.

In 1940, in his first speech to the House of Commons as British prime minister, Winston Churchill said, “I have nothing to offer but blood, toil, tears and sweat.”

In 1985, a confrontation between Philadelphia authorities and the radical group MOVE ended as a police helicopter dropped two bombs onto the group’s row house, igniting a fire that killed 11 people (including five children) and destroyed 61 homes.

In 2016, the Obama administration issued a directive requiring public schools to permit transgender students to use bathrooms and locker rooms consistent with their chosen gender identity.