Csanád Telegdi was born into the ancient Hungarian "gens" Csanád around 1280, as one of the four sons of "comes" Thomas. The namesake founder of the clan was the nephew of the first Hungarian king Stephen I of Hungary, who sent his relative to defeat the rebellious lord Ajtony around 1030. Thereafter Csanád County and its capital, in addition to the clan, was named after him. The Telegdis' first known direct ancestors are Benedict (or Belenig) and his son, Clement (also Kelemenes), the "ispán" of Arad County in the early 13th century. Csanád's father Thomas was an educated man with the title of "magister". He had various conflicts with the Cuman tribes, who lived in Temes. He left his estates in Csanád County in the 1290s and moved to Bihar County, establishing his manor seat in Telegd (present-day Tileagd, Romania). His descendants took their surname after the village. Csanád had three brothers: Lawrence I, Nicholas I, "ispán" of various counties, who fought in the Battle of Rozgony, and Pancras, the father of Thomas Telegdi, also an archbishop of Esztergom. Csanád also had two unidentified sisters: one of them married vice-voivode Nicholas Vásári, their son was Nicholas, Csanád's immediate successor in the archiepiscopal seat of Esztergom. Csanád's second sister was the wife of a certain Michael, they had a son named Stephen.