The battle began on 23 June as the English army attempted to force its way across the high ground of the Bannock Burn, which was surrounded by marshland. Skirmishing between the two sides broke out, resulting in the death of Sir Henry de Bohun, whom Robert killed in personal combat. Edward continued his advance the following day, and encountered the bulk of the Scottish army as they emerged from the woods of New Park. The English appear not to have expected the Scots to give battle here, and as a result had kept their forces in marching, rather than battle, order, with the archers − who would usually have been used to break up enemy spear formations − at the back, rather than the front, of the army. The English cavalry found it hard to operate in the cramped terrain and were crushed by Robert's spearmen. The English army was overwhelmed and its leaders were unable to regain control.