He was the younger son of Ramon Berenguer III, Count of Barcelona, and Douce I, Countess of Provence.
In 1132, Berenguer was in a succession war against Alfonso Jordan, Count of Toulouse, over the county of Melgueil.
[2] Alfonso was defeated and Berenguer married Beatrice, heiress of Melgueil.
[1] His reign was occupied in wars with the family of Baux, which claimed the county of Provence.
[2] His son Raymond Berengar succeeded him in Provence,[1] but the county of Melgueil went to Beatrice' second husband, Bernard V Pelet, and their daughter Ermessende of Pelet.