Conrad of Antioch was a scion of an illegitimate branch of the imperial Staufer dynasty and a nobleman of the Kingdom of Sicily. He was the eldest son of Frederick of Antioch, imperial vicar of Tuscany, and Margherita di Poli. He was thus a grandson of the Emperor Frederick II, a nephew of King Manfred of Sicily (1258–66) and cousin of King Conradin (1266–68). His surname, which is contemporary, comes from his paternal grandmother, a mistress of Frederick II from Antioch. He may be called "Conrad I" to distinguish him from his descendants with the same given name.

The Hohenstaufen dynasty, also known as the Staufer, was a noble family of unclear origin that rose to rule the Duchy of Swabia from 1079, and to royal rule in the Holy Roman Empire during the Middle Ages from 1138 until 1254. The dynasty's most prominent rulers – Frederick I (1155), Henry VI (1191) and Frederick II (1220) – ascended the imperial throne and also reigned over Italy and Burgundy. The non-contemporary name of 'Hohenstaufen' is derived from the family's Hohenstaufen Castle on Hohenstaufen mountain at the northern fringes of the Swabian Jura, near the town of Göppingen. Under Hohenstaufen rule, the Holy Roman Empire reached its greatest territorial extent from 1155 to 1268.