After a long winter, the Lewis and Clark expedition departs its camp among the Mandan tribe and resumes its journey West.

On April 7, 1945, the Japanese battleship Yamato, one of the greatest battleships of its time, is sunk in Japan’s first major counteroffensive in the struggle for Okinawa.

President Harry S. Truman receives National Security Council Paper Number 68 (NSC-68). The report was a group effort, created with input from the Defense Department, the State Department, the CIA, and other interested agencies; NSC-68 formed the basis for America’s Cold War policy for the next two decades.

By a vote of 57 to 1, Dag Hammarskjöld is elected secretary-general of the United Nations.

On April 7, 1961, President John F. Kennedy sends a letter to Congress in which he recommends the U.S. participate in an international campaign to preserve ancient temples and historic monuments in the Nile Valley of Egypt. The campaign, initiated by UNESCO, was designed to save sites threatened by the construction of the Aswan High Dam.

On April 7, 1970, the legendary actor John Wayne wins his first—and only—acting Academy Award, for his star turn in the director Henry Hathaway’s Western True Grit.

On April 7, 1994, violence fuels the launch of what would become the worst episode of genocide since World War II: the massacre of an estimated 500,000 to 1 million innocent civilian Tutsis and moderate Hutus. Following the first wave of massacres, Rwandan forces manage to discourage international intervention with the murder of 10 Belgian peacekeeping officers. The Tutsis, a minority group that made up about 10 percent of Rwanda’s population, received no assistance from the international community, although the United Nations later conceded that a mere 5,000 soldiers deployed at the outset would have stopped the wholesale slaughter.