Complex sentence: In 1247 he married Henry III's half-sister Alice le Brun de Lusignan, a marriage that created resentment amongst the English nobility, who did not like seeing a wealthy English nobleman marrying a penniless foreigner.
Split into simpler sentences: In 1247 he married Henry III's half-sister Alice le Brun de Lusignan. This marriage was to create resentment amongst the English nobility, who did not like seeing a wealthy English nobleman marrying a penniless foreigner.