Complex sentence: Many of the leading Livery companies had been re-organized, with new Charters of Incorporation, during Henry VIII's reign: the new aldermen of Edward's reign and Protectorate represented their interests in the City's governance in expectation of future Protestant succession to the English throne.
Split into simpler sentences: Many of the leading Livery companies had been re-organized, with new Charters of Incorporation, during Henry VIII's reign. The aldermen of Edward's reign and Protectorate engaged in the City's governance in anticipation of Protestant succession to the English throne.