Moldova occupies most of what has been known as Bessarabia.
Moldova's location has made it a historic passageway between Asia
and southern Europe, as well as the victim of frequent warfare. Greeks,
Romans, Huns, and Bulgars invaded the area, which in the 13th century
became part of the Mongol empire. An independent Moldovan state
emerged briefly in the 14th century but fell under Ottoman Turkish rule
in the 16th century.
 
After the Russo-Turkish War of 1806-12, the eastern half of Moldova
(Bessarabia) between the Prut and the Dniester Rivers was ceded to
Russia, while Romanian Moldova (west of the Prut) remained with the
Turks. Romania, which gained independence in 1878, took control of
the Russian half of Moldova in 1918. The Soviet Union never
recognized the seizure and created an autonomous Moldavian republic
on the east side of the Dniester River in 1924.
 
In 1940, Romania was forced to cede eastern Moldova to the U.S.S.R.,
which established the Moldavian Soviet Socialist Republic. Romania
sought to regain it by joining with Germany in the 1941 attack on the
U.S.S.R. Moldova was ceded back to Moscow when hostilities between
the U.S.S.R. and Romania ceased at the end of World War II. The
present boundary between Moldova and Romania was established in
1947. Moldova declared independence from the Soviet Union on
August 27, 1991.
source: State Department Background Notes 1996