The Kingdom of Lithuania was a Lithuanian monarchy which existed from 1251 to roughly 1263.
The status of a kingdom was granted by Pope Innocent IV, when the state was placed under the jurisdiction of the Bishop of Rome, on July 17, 1251. Two years later, the Lithuanian ruler Mindaugas was crowned as the King of Lithuania. In 1259, Mongols under Burundai invaded the southern border of the kingdom, sacking a few towns and defeating a Lithuanian army.[1] After the assassination of Mindaugas and his sons in 1263, the country reverted to paganism, and its status of a kingdom was lost.
There was also an attempt by Vytautas the Great (ruled 1401–1430) to receive a royal crown. He was proclaimed king, and Lithuania a kingdom, by Emperor Sigismund, Holy Roman Emperor in 1430, but the royal crown, which was sent by Sigismund to Vytautas, was intercepted by Polish noblemen. Soon afterwards Vytautas died, without being crowned as king.
In 1918, a Kingdom of Lithuania was briefly created as a German client-state, with Mindaugas II as King of Lithuania. Following Germany's defeat in World War I a few months later, the kingdom was superseded by the Act of Independence of Lithuania.