Deal Castle was seized by Parliamentary forces at the start of the first English Civil War between the supporters of King Charles I and Parliament, resulting in the dismissal of Byng as a suspected Royalist and his replacement by Colonel Rainsborough, a vice-admiral.[31] The castle did not play a significant role in the remainder of the initial conflict.[32] After the few years of unsteady peace after 1645, the Second Civil War broke out in 1648, this time with Charles' Royalist supporters joined by their Scottish allies.