Peter I of Trani

Peter or Pierron (born before 1020) was the first Norman lord of Trani, a town on the Adriatic near Barletta. He was one of the most prominent of the twelve leaders of the Normans of mercenaries of Guaimar IV of Salerno and received Trani in the division at Melfi of the Apulian conquests. It is unknown if Peter was in fact a Norman, he may have been a Breton or Frenchman.

Peter participated in the campaign of George Maniaches in Sicily in 1038. He was always close by the side of William Iron Arm himself, the leader and first count of the Normans of Melfi. He was a candidate for successor of William in 1046. During the reign of William and his successor, Drogo, Peter fortified the region around Trani with fortresses at Andria, Bisceglie, Barletta, and Corato.

Peter was a thorn in the side of William's brother Robert Guiscard during his reign (1057–1085). Peter was alive in January 1073 and that is his last appearance in history.