Coordinates: 53°56′31″N 1°05′53″W / 53.94204°N 1.09812°W / 53.94204; -1.09812

The Knavesmire is one of a number of large, marshy undeveloped areas within the city of York in North Yorkshire, England, which are collectively known as Strays. Knavesmire, together with Hob Moor, comprises Micklegate Stray.

It has been suggested that the name 'Knavesmire' may share a derivation with Knaresborough -- Cenward's mire.

Situated in the south-west of the city, some distance outside the historic walls, Knavesmire's low-lying position makes it liable to severe flooding in times of heavy rain. As a consequence, it remained undeveloped as the city expanded around it.

For many years, Knavesmire was the site of public hangings in York. The gallows were erected in 1379, a few miles outside the city on the main southern approach road (now known as the A1036 Tadcaster Road). Probably the most famous people to be executed there were Rhys ap Maredudd, a Welsh nobleman and rebel, hanged in 1292, and Dick Turpin, who was hanged in 1739. By the beginning of the 19th century, it was felt that the gallows did not create a good first impression for visitors to the city. The last hanging at Knavesmire was in 1801, after which the gallows were moved to a more discreet (although still public) location near the castle. A paved area with a small plaque today marks the position in which the scaffold stood.

Guy Fawkes (13 April 1570 – 31 January 1606), also known as Guido Fawkes, the name he adopted while fighting for the Spanish in the Low Countries, belonged to a group of provincial English Catholics who planned the failed Gunpowder Plot of 1605.

Fawkes was born and educated in York. His father died when Fawkes was eight years old, after which his mother married a recusant Catholic. Fawkes later converted to Catholicism and left for the continent, where he fought in the Eighty Years' War on the side of Catholic Spain against Protestant Dutch reformers. He travelled to Spain to seek support for a Catholic rebellion in England but was unsuccessful. He later met Thomas Wintour, with whom he returned to England.

Wintour introduced Fawkes to Robert Catesby, who planned to assassinate King James I and restore a Catholic monarch to the throne. The plotters secured the lease to an undercroft beneath the House of Lords, and Fawkes was placed in charge of the gunpowder they stockpiled there. Prompted by the receipt of an anonymous letter, the authorities searched Westminster Palace during the early hours of 5 November, and found Fawkes guarding the explosives. Over the next few days, he was questioned and tortured, and eventually he broke. Immediately before his execution on 31 January, Fawkes jumped from the scaffold where he was to be hanged and broke his neck, thus avoiding the agony of the mutilation that followed.