1741 - Frederick II of Prussia defeated Maria Theresa's forces at Mollwitz and conquered Silesia.
1790 - The U.S. patent system was established.
1809 - Austria declared war on France and its forces entered Bavaria.
1814 - Napoleon was defeated at the Battle of Toulouse by the British and the Spanish. The defeat led to his abdication and exile to Elba.
1825 - The first hotel opened in Hawaii.
1849 - Walter Hunt patented the safety pin. He sold the rights for $100.
1902 - South African Boers accepted British terms of surrender.
1912 - The Titanic set sail from Southampton, England.
1930 - The first synthetic rubber was produced.
1932 - Paul von Hindenburg was elected president of Germany with 19 million votes. Adolf Hitler came in second with 13 million votes.
1938 - Germany annexed Austria. 99.75 percent of Austrians had voted in a referundum to merge with Germany.
1941 - In World War II, U.S. troops occupied Greenland to prevent Nazi infiltration.
1944 - Russian troops recaptured Odessa from the Germans.
1959 - Japan's Crown Prince Akihito married commoner Michiko Shoda.
1980 - Spain and Britain agreed to reopen the border between Gibraltar and Spain. It had been closed since 1969.
1981 - Imprisoned IRA hunger striker Bobby Sands was elected to the British Parliament.
1994 - NATO warplanes launched air strikes for the first time on Serb forces that were advancing on the Bosnian Muslim town of Gordazde. The area had been declared a U.N. safe area.
1998 - Negotiators reached a peace accord on governing British ruled Northern Ireland. Britain's direct rule was ended.
2001 - The Netherlands legalized mercy killings and assisted suicide for patients with unbearable, terminal illness.