–13th century until 1569. In 1569 it became a part of the Polish–Lithuanian Commonwealth until 1791. It was started by the Lithuanians. The duchy grew to include large parts of the former Kievan Rus' and other Slavic lands. It covered the land of present-day Belarus, Latvia, Lithuania and parts of Estonia, Moldova, Poland, Russia and Ukraine. At its biggest in the 15th century, it was the largest state in Europe. There was great diversity in languages, religion, and cultural heritage.