The Battle of Muster Green (also known as the Battle of Haywards Heath) was a minor battle of major significance that took place during the first week of December 1642 on and around the then much larger Muster Green in Haywards Heath during the first year of the First English Civil War. A Royalist army under Colonel Edward Ford, High Sheriff of Sussex, marching from Chichester to seize Lewes for the King encountered a smaller but more disciplined Parliamentarian army under Colonel Herbert Morley waiting for them on Muster Green.
After Royalist musketeers fired "some" volleys, Morley's cavalry broke through the Royalist's advanced guard and, with the Parliamentarian infantry charging simultaneously, fought hand-to-hand; at least an hour of fighting ensued in which 200 Royalists were killed, wounded, or captured, resulting in the surviving Royalist forces' routing and the Parliamentarians emerging victorious, saving Lewes from a Royalist assault, and pushing back Ford's 1642 Royalist invasion of Sussex. The battle site of the Battle of Muster Green became and remained the furthest any large Royalist force advanced through Sussex during the English Civil Wars.
Background
At the beginning of the First English Civil War there was no obvious distinction by location, occupation, or social class that outlined who would declare their support for the Royalists and who would declare support for the Parliamentarians in Sussex. Although historians have tried to characterise the eastern half of the county as "staunchly Parliamentarian" and western parts as more sympathetic to the Royalist cause, this broad distinction obscures many localised variations, particularly in downland areas and some urban areas. For example, in Chichester, the church, gentry, and upper classes made clear their support was for Charles I while the rising merchant classes showed their sympathies lay with the Parliamentarians. The people of poorer standing, while making up the majority of the population, were much less eager to take up the cause of either side.
It was soon clear that neither Royalists nor Parliamentarians would have control of Sussex without the use of force via a military campaign through the county. Sussex was of strategic and industrial importance to both sides during the war due to the cannon foundries and ironworks making up the Wealden iron industry in the High Weald, controlling which would have given a logistical advantage to the side that controlled them, and also because the Sussex coastline was one of the shortest routes to France – potentially a source of smuggled arms, gunpowder, troops, and bullion, as well as other equipment and materials required to wage and win a civil war. The proximity to France also meant the county could be used as an escape route by the King – another factor which made Sussex "a region that Parliament needed to keep under firm control".
In wider context, when the King fled to Oxford in August 1642 after he raised his royal standard in Nottingham and officially started the First English Civil War, he held the north of England, most of the Midlands, the south west of England, and Wales. This meant that it was mostly obvious where strong Royalist support began and ended and, with Sussex, part of this 'front line' was at the boundary with itself and Hampshire (even though Hampshire was mostly sympathetic to Parliament, the Royalists held many isolated strongholds in the county such as Portsmouth, Basing House, and Winchester). Edward Ford, the Royalist leader at the battle, had been given a colonel's commission at the outbreak of war by Charles, who also made Ford the High Sheriff of Sussex in 1642. Ford offered his majesty "a thousand men, and to undertake the conquest of Sussex, though sixty miles in length" and began to raise forces accordingly. On 18 November 1642, Ford marched his Royalist army from Hampshire across the border with, and into, Sussex, whereupon he seized Chichester for the King. Ford then set his eyes on Lewes.