During the 14th century, Lithuania was the largest country in Europe, as present-day Belarus, Ukraine, and parts of Poland and Russia were territories of the Grand Duchy of Lithuania. With the Lublin Union of 1569 Poland and Lithuania formed a new state: the Polish–Lithuanian Commonwealth, which was finally destroyed by its neighboring countries in 1795. Most of Lithuania's territory was annexed by the Russian Empire, until the Act of Independence was signed on 16 February 1918, which declared the re-establishment of a sovereign state. Between 1940 and 1945 Lithuania was occupied by both the Soviet Union and Nazi Germany at different times. When World War II was near its end in 1944 and the Nazis retreated, the Soviet Union reoccupied Lithuania. On 11 March 1990, Lithuania became the first Baltic republic to declare its restored independence after 50 years of Soviet occupation.
Lithuania became a full member of the Schengen Agreement on 21 December 2007.[3] In 2009, Lithuania celebrated the millennium of its name.