Wales was overwhelmingly Royalist in the Wars of the Three Kingdoms in the early 17th century though there were some notable exceptions such as John Jones Maesygarnedd and the Puritan writer Morgan Llwyd. Wales was an important source of men for the armies of King Charles I of England, though no major battles took place in Wales. The Second English Civil War began when unpaid Parliamentarian troops in Pembrokeshire changed sides in early 1648. Colonel Thomas Horton defeated the Royalist rebels at the battle of St. Fagans in May and the rebel leaders surrendered to Cromwell on 11 July after the protracted two-month siege of Pembroke.