Conrad (25 March 1252 – 29 October 1268), called
the Younger or
the Boy, but usually known by the diminutive
Conradin (, ), was the
Duke of Swabia (1254–1268, as
Conrad IV),
King of Jerusalem (1254–1268, as
Conrad III), and
King of Sicily (1254–1258,
de jure until 1268, as
Conrad II).