Lithuania Minor, or Prussian Lithuania, is a historical ethnographic region of Prussia, where Prussian Lithuanians lived, now located in Lithuania and the Kaliningrad Oblast of Russia. Lithuania Minor encompassed the northeastern part of the region and got its name from the territory's substantial Lithuanian-speaking population. Prior to the invasion of the Teutonic Knights in the 13th century, the main part of the territory later known as Lithuania Minor was inhabited by the tribes of Skalvians and Nadruvians. The land depopulated during the incessant war between Lithuania and the Teutonic Order. The war ended with the Treaty of Melno and the land was repopulated by Lithuanian newcomers, returning refugees, and the remaining indigenous Baltic peoples; the term Lithuania Minor appeared for the first time between 1517 and 1526.

Lithuanian is an East Baltic language belonging to the Baltic branch of the Indo-European language family. It is the language of Lithuanians and the official language of Lithuania as well as one of the official languages of the European Union. There are approximately 2.8 million native Lithuanian speakers in Lithuania and about 1 million speakers elsewhere. Around half a million inhabitants of Lithuania of non-Lithuanian background speak Lithuanian daily as a second language.