Helped by the Scots, Parliament won at Marston Moor (2 July 1644), gaining York and the north of England. Cromwell's conduct in the battle proved decisive, and showed his potential as a political and as an important military leader. The defeat at the Battle of Lostwithiel in Cornwall, however, marked a serious reverse for Parliament in the south-west of England. Subsequent fighting around Newbury (27 October 1644), though tactically indecisive, strategically gave another check to Parliament.