History

Magna Carta
It could be argued that the road to Chesterfield in 1266 began at Runnymede in 1215, when the Barons forced King John to set his seal to Magna Carta. You can read more about the link here.

To get started, here is the Wikipedia article about the battle of Chesterfield.
If you can supply any more information, do get in touch - info@chesterfield750.co.uk

The Battle of Chesterfield was a minor skirmish in the latter stages of 13th century England's Second Barons' War.[1] It was part of the “mopping up” of Baronial opposition that resisted Henry III following the Battle of Evesham. The fighting took place in, and around, Chesterfield, Derbyshire on 15 May 1266.[2] The leaders of the Barons were Robert Ferrers, Earl of Derby, Baldwin Wake, Lord of Chesterfield and John d’Ayville. The Royalist forces were led by Henry of Almain, nephew to Henry III.
There are several references to aspects of the battle in chronicles from the period. Thomas Wykes, in his “Chronicon Thomae Wykes”[3] mentions the royalist forces using covered wagons to gain entry to the town.
A reference[2] also exists to explain how “the men of Brampton” (a suburb of Chesterfield) rushed to the church at the time of the battle and defended that part of the wall for which they were responsible. Presumably, it would fall to them to repair any damage and they were keen to avoid such costs!
Wykes also explains how Ferrers was stricken by gout at the time of the battle and that the Barons’ leader was “taken ignobly.” It is likely that he was captured in the church.[4] Legend has it that he was betrayed by a woman of the town but there is no documentary evidence for this claim; nor is there evidence for the assertion that Ferrers was hiding under sacks of wool stored in the church.
According to the Chronicles of Walter of Guisborough,[5] John D’Eyvile forced his way through the enemy and unhorsed Sir Gilbert Haunsard with his lance, before wounding several others and making his escape. D’Eyvile was later at the Siege of Kenilworth before surrendering.
Baldwin Wake also escaped the fighting and joined with other disinherited Barons at the Isle of Axholme[5] before eventually surrendering to Prince Edward, the future Edward I.
Following his capture, Robert Ferrers was taken “in irons”[3] to London and, at the Westminster parliament later that year, was “totally disinherited.”[2]

References
1 Bestall, J M (1974). History of Chesterfield. Borough of Chesterfield. ISBN 0 9500459 5 0.
2 Pegge, Samuel (1769). "A succinct and authentic narrative of the Battle of Chesterfield, A.D 1266 in the reign of King Henry III". Archaeologica. XXXVI: 276–285.
3 Wykes, Thomas. "Chronico Thomae Wykes". In Luard, Henry Richard. The Rolls Series Annales Monastici vol iv (1869).
4 Knighton, Henry. Lumby, J R (1889), ed. Knighton’s Chronicon.
5 Walter of Guisborough. Chronicles of Walter of Guisborough.

For a summary of the contemporary accounts of the battle, you can read an article written in 1771 by Sammuel Pegge here. It makes clear that there is no agreement on what actually happened all those years ago!