Frederick married Isabel Of ENGLAND on 20 Jul 1235 in Worms. Isabel (daughter of John 'Lackland' King Of ENGLAND and Isabella Of ANGOULEME) was born in 1214 in Gloucester, England; died on 01 Dec 1241 in Fogia, Apulia, Italy; was buried in Andria, Bari, Apulia, Italy. [Group Sheet] [Family Chart]