An event in history for today April 30th happened in 1900 when the U.S. annexed Hawaii.
Alexander I became king of Greece today, 30th of May in 1917. Many, many things happened in history on May 30th. The Indianapolis 500 is often today with the most recent winner on May 30th being Dario Franchitti in 2010.
On March 30, 1945, Austria was invaded by the USSR.
On June 30, 1965, the Atlanta Falcons became a franchise.
Many things have happened on March 30th, I've included a link in the 'sources and related links section' (see below).
On August 30, 1945, the Japanese was liberated from Hong Kong.
The historical event that occurred On 30th May was the death of Agostino Di Bartolomei, Italian footballer (b. 1955) Ted Drake, in 1995, who was both an English footballer and manager.
On September 30th in history, the city of New York was established in 1898.
On March 30, 1867, the United States bought Alaska from Russia.
Yes, there are several things that happened on the 30th of November that is noteworthy. In 1950, President Truman said that he was prepared to authorize the use of atomic weapons if that is what it will take to achieve peace in Korea.
On April 30, 1900, The United Stated annexed Hawaii.
The following events happened in history on the 30th of November. In 2004, Ken Jennings lost after 75 appearances on Jeopardy!, in 2006, Pope Benedict visited one of Turkey's most famous mosques, and in 2011, Great Britain withdraws diplomats from Iran.