The New Model Army was created in February 1645 by Parliament as it felt that a professional army would be more successful against the king's army. ... Cromwell had already made his mark at the Battle of Marston Moor where his cavalry had done a lot of damage to the king's army.
When Alexius I Komnenoi implored the pope (Urban II) for help, he meant it to reconquer the lost Byzantine lands (and therefore return in to their de facto ruler, a.k.a., the Byzantines). Urban however, decided to merely use that as a façade in order to then invade the Muslims, and retake the holy land.
He also saw the wanted to unite Christianity as a whole (All the sects at the time, Orthodoxy, Catholicism, Paulicianism, Iconoclasts, etc. into a single conglomerate, fighting a common enemy.)
