Complex sentence: The original Earldom of Desmond, based on land holdings in Munster belonged the Cambro-Norman FitzGerald dynasty, which was founded by Maurice FitzGerald, a key supporter of Lord Pembroke ("Strongbow") in his invasion of Ireland.
Split into simpler sentences: The original Earldom of Desmond, based on land holdings in Munster, belonged to the Cambro-Norman FitzGerald dynasty, which was founded by Maurice FitzGerald. FitzGerald was a key supporter of Lord Pembroke ("Strongbow") in his invasion of Ireland.