High Quality Content by WIKIPEDIA articles! Lithuania proper (Latin: Lithuania propria; Lithuanian: Didzioji Lietuva, literally: "Genuine Lithuania"; Yiddish: ליטע, Lite) refers to a region which existed within Grand Duchy of Lithuania, and spoke Lithuanian language. The primary meaning is identical to the Duchy of Lithuania, a land around which Grand Duchy of Lithuania evolved. The territory can be traced by Catholic Christian parishes established in pagan Baltic lands of the Grand Duchy of Lithuania subsequent to the Christianization of Lithuania in 1387. They were quite distinguishable, as the Ruthenian parts of the Duchy were already baptised in orthodox manner. The term in Latin was widely used during the Middle Ages and can be found in numerous historical maps until World War I.