1539 – Emperor Charles V reached a truce with German Protestants at Frankfurt, Germany.

1587 – English admiral Sir Francis Drake entered Cadiz harbor and sank the Spanish fleet.

1764 – The English Parliament banned the American colonies from printing paper money.

1770 – Captain James Cook discovered New South Wales, Australia. Cook originally named the land Point Hicks.

1775 – The American Revolution began as fighting broke out at Lexington, MA.

1782 – The Netherlands recognized the new United States.

1794 – Tadeusz Kosciuszko forced the Russians out of Warsaw.

1839 – The Kingdom of Belgium was recognized by all the states of Europe when the Treaty of London was signed.

1861 – U.S. President Lincoln ordered a blockade of Confederate ports.

1943 – The Warsaw Ghetto uprising against Nazi rule began. The Jews were able to fight off the Germans for 28 days.

1951 – General Douglas MacArthur gave his “Old Soldiers” speech before the U.S. Congress after being relieved by U.S. President Truman. In the address General MacArthur said that “Old soldiers never die, they just fade away.”

1956 – Actress Grace Kelly became Princess Grace of Monaco when she married Prince Rainier III of Monaco. The civil ceremony took place on April 18.

1967 – Surveyor 3 landed on the moon and began sending photos back to the U.S.

1971 – Russia launched the Salyut into orbit around Earth. It was the first space station.

1975 – India launched its first satellite with aid from the USSR.

1982 – NASA named Sally Ride to be first woman astronaut.

1982 – NASA named Guion S. Bluford Jr. as the first African-American astronaut.

1989 – A gun turret exploded aboard the USS Iowa. 47 sailors were killed.

1989 – A giant asteroid passed within 500,000 miles of Earth.

1989 – In El Salvador, Attorney General Alvadora was killed by a car bomb.

2000 – In the Philippines, Air Philippines GAP 541 crashed while preparing to land. 131 people were killed.

2002 – The USS Cole was relaunched. In Yemen, 17 sailors were killed when the ship was attacked by terrorists on October 12, 2000. The attack was blamed on Osama bin Laden’s al-Qaida network.