Charles XIII and II also Carl, Swedish: Karl XIII (October 7, 1748 – February 5, 1818), is King of Sweden (as Charles XIII) from 1809 and King of Norway (as Charles II) from 1814 until his death.

He is the second son of King Adolf Frederick of Sweden and Louisa Ulrika of Prussia, sister of Frederick II of Prussia.

Though known as King Charles XIII in Sweden, he is actually the seventh Swedish king by that name, as Charles IX (reigned 1604–1611) had adopted his numeral after studying a fictitious history of Sweden.