When it became apparent to the leaders of the New Model Army that Parliament—then controlled by the Presbyterian faction—was ready to come to an agreement with the King that would restore him to the throne (though without effective power) and negate the power of the Army, they resolved to shatter the power of both King and Parliament.
Kui Uue Musterarmee juhid mõistsid, et parlament, mis tollal kontrollis presbüterlik fraktsioon, oli valmis sõlmima kuningaga lepingu, mis aitaks ta uuesti troonile (ehkki sisulise võimuta) ning eemaldaks võimult armee, otsustasid nad purustada nii kuninga kui ka parlamendi.