context: The historical period of Lithuanian history is considered to have started in 1009, when the name of Lithuania was first mentioned in written sources. [1] Lithuanians established the Kingdom of Lithuania in the 13th century. The later Grand Duchy of Lithuania remained strictly independent of the other kingdoms and was one of the last European countries to convert to Christianity. In the 15th century, Poland-Lithuania became the largest nation in Europe. [2] However, during the partitions of Poland in 1772, 1793 and 1795, Poland-Lithuania was disintegrated and Lithuania became part of the Russian Empire. [3]
question: In what year was Lithuania established?
answers.text: 13th century