Complex sentence: Baptists, Congregationalists, Methodists, and Quakers were all allowed to pray freely, although many of these groups had taken the opportunity of the expanding empire and had set themselves up in the Thirteen Colonies, where they expanded rapidly after the First Great Awakening.
Split into simpler sentences: Baptists, Congregationalists, Methodists, and Quakers were all allowed to pray freely. These groups took the opportunity of the expanding empire and set up in the Thirteen Colonies, where they expanded rapidly after the First Great Awakening.