Matthew III Csák
Peter (I) from the kindred Csák (; "c". 1240 – 1283 or 1284) was a powerful Hungarian baron, landowner and military leader, who held several secular positions during the reign of kings Stephen V and Ladislaus IV. His son and heir was the oligarch Matthew III Csák, who, based on his father and uncles' acquisitions, became the "de facto" ruler of his domain independently of the king and usurped royal prerogatives on his territories.