Complex sentence: During the Army's formation, some Presbyterians considered it a hotbed of Independents, a potentially dangerous situation given that Parliament's agreement with the Scottish Covenanters stipulated that Presbyterianism was to be made the established Church in England.
Split into simpler sentences: During the Army's formation, some Presbyterians considered it a hotbed of Independents, a potentially dangerous situation. The Parliament's agreement with the Scottish Covenanters stipulated that Presbyterianism was to be made the established Church in England.