Original: By the 11th century, Transylvania became a largely autonomous part of the Kingdom of Hungary, and became independent as the Principality of Transylvania from the 16th century, until 1711.
Simplified: The Bulgarians held Transylvania until the 11th century. Transylvania belonged to the Kingdom of Hungary from around the 10th century until the 16th century, when it turned into the Principality of Transylvania.