Correct, well done. I put it forward thinking that all the parliamentarians would have remembered this date and known the answer!
No names mentioned
In March 1643, a large force of Royalists from Newark commanded by Sir Charles Cavendish and Sir John Henderson marched into Lincolnshire and captured the town of Grantham in a surprise attack. The Royalists did not garrison Grantham but marched on towards Boston. Parliament's commander in Lincolnshire, Lord WIlloughby of Parham, attempted to block the Royalist advance with a force of 1,500 troops, but in a brief engagement at Ancaster Heath on 11 April, the Parliamentarians were easily routed by the larger Royalist force.
Alarmed that Cavendish's manoeuvres might herald a march south by the Earl of Newcastle's northern army, Parliament ordered Lord Willoughby to make another attack on Newark. Willoughby joined forces with Colonel Cromwell of the Eastern Association and Captain Hotham with a contingent from Nottingham at Sleaford on 9 May. They advanced to Grantham on 11 May but remained there for a further two days, which gave Cavendish and Henderson time to prepare a counterstrike. In the early hours of 13 May, Cavendish made a surprise attack on Lord Willoughby's troops quartered at the village of Belton, killing 70 and taking 40 prisoners. Later in the day, the Royalists made a second advance. After an exchange of musket fire, Cromwell, in his first independent action as a cavalry commander, led a charge that drove the Royalists from the field. Despite the Parliamentarian victory, however, the march on Newark was abandoned.
Pete 
