Conrad III, called the Younger or the Boy, but usually known by the diminutive Conradin, was the last direct heir of the House of Hohenstaufen. He was Duke of Swabia (1254–1268) and nominal King of Jerusalem (1254–1268) and Sicily (1254–1258). After his attempt to reclaim the Kingdom of Sicily for the Hohenstaufen dynasty failed, he was captured and beheaded.

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.