Lithuania is the largest and most southern of the three former Soviet Baltic republics. But unlike Latvia and Estonia, Lithuania has had a long tradition of independence. By the mid-13th century Lithuania extended from the Baltic to the Black Sea, and was a major regional power. Close political association with Poland led to a merger in 1569, but the joint state was dissolved in 1795 and Lithuania was incorporated into the Russian Empire. Lithuania regained its independence following World War I, but during World War II it was overtaken by the Soviet Union and became a republic of the USSR in 1940. In 1990 Lithuania became the first of the Soviet republics to declare its independence, although Moscow did not recognize this proclamation until September of 1991. Lithuania initiated economic reforms upon independence aimed at moving from a command economy to a free-market one, and the country joined the EU in May 2004. Its economic performance over much of the past decade has been impressive, but the economy was hard hit by the global financial crisis of 2008.