Confirmed his father's gifts to the abbey of St. Florent in 1096. He was the first Braose Lord of Builth and Radnor, their initial holding in the Welsh Marches. Philip seems to have gone on the 1st Crusade and returned in 1103. He built the Norman church of St Nicolas at Old Shoreham and founded the port of New Shoreham. His lands were confiscated by Henry I in 1110, due to his traitrous support of William, son of Robert Curthose but they were returned in 1112. Between 1125 and 1130 Philip confirmed the gifts of his nephew, Philip de Harcourt, to the newly established Knights Templar