June 14, 1775 - The first U.S. Military service, the Continental Army consisting of six companies of riflemen, was established by the Second Continental Congress. The next day, George Washington was appointed by a unanimous vote to command the army.
June 14, 1777 - John Adams introduced a resolution before Congress mandating a United States flag, stating, "...that the flag of the thirteen United States shall be thirteen stripes, alternate red and white; that the union be thirteen stars, white on a blue field, representing a new constellation." This anniversary is celebrated each year in the U.S. as Flag Day.
June 14, 1922 - Warren G. Harding became the first U.S. President to broadcast a message over the radio. The event was the dedication of the Francis Scott Key Memorial in Baltimore.
June 14, 1951 - Univac 1, the world's first commercial electronic computer was unveiled in Philadelphia. It was installed at the Census Bureau and utilized a magnetic tape unit as a buffer memory.
June 17, 1972 - Following a seemingly routine burglary, five men were arrested at the National Democratic Headquarters in the Watergate complex in Washington, D.C. However, subsequent investigations revealed the burglars were actually agents hired by the Committee for the Re-election of President Richard Nixon. A long chain of events then followed in which the president and top aides became involved in an extensive cover-up of this and other White House sanctioned illegal activities, eventually leading to the resignation of President Nixon on Aug. 9, 1974.
June 18, 1812 - After much debate, the U.S. Senate voted 19 to 13 in favor of a declaration of war against Great Britain, prompted by Britain's violation of America's rights on the high seas and British incitement of Indian warfare on the Western frontier. The next day, President James Madison officially proclaimed the U.S. to be in a state of war. The War of 1812 lasted over two years and ended with the signing of the Treaty of Ghent in Belgium on December 24, 1814.
June 18, 1815 - On the fields near Waterloo in central Belgium, 72,000 French troops, led by Napoleon, suffered a crushing military defeat from a combined Allied army of 113,000 British, Dutch, Belgian, and Prussian troops. Thus ended 23 years of warfare between France and the other powers of Europe. Napoleon was then sent into exile on the island of St. Helena off the coast of Africa. On May 5, 1821, the former vain-glorious Emperor died alone on the tiny island, abandoned by everyone.
June 18, 1983 - Dr. Sally Ride, a 32-year-old physicist and pilot, became the first American woman in space, beginning a six-day mission aboard the space shuttle Challenger, launched from Cape Canaveral, Florida.
June 19, 1953 - Julius and Ethel Rosenberg were executed by electrocution at Sing Sing Prison in New York. They had been found guilty of providing vital information on the atomic bomb to the Soviet Union during 1944-45. They were the first U.S. civilians to be sentenced to death for espionage and were also the only married couple ever executed together in the U.S.
June 20, 1782 - The U.S. Congress officially adopted the Great Seal of the United States of America.
June 21, 1964 - Three white civil rights workers – James Chaney, Andrew Goodman and Michael Schwerner – left Meridian, Miss., at 9 a.m. to investigate a church burning. They were expected back by 4 p.m. When they failed to return, a search was begun. Their murdered bodies were discovered on August 4.