The Battle of Naseby took place on 14 June 1645 during the First English Civil War, near the village of Naseby in Northamptonshire. The Parliamentarian New Model Army, commanded by Sir Thomas Fairfax and Oliver Cromwell, destroyed the main Royalist army under Charles I and Prince Rupert. Defeat ended any real hope of Royalist victory, although Charles did not finally surrender until May 1646.
The 1645 campaign began in April when the newly formed New Model Army marched west to relieve Taunton, before being ordered back to lay siege to Oxford, the Royalist wartime capital. On 31 May, the Royalists stormed Leicester and Fairfax was instructed to abandon the siege and engage them. Although heavily outnumbered, Charles decided to stand and fight and after several hours of combat, his force was effectively destroyed. The Royalists suffered over 1,000 casualties, with over 4,500 of their infantry captured and paraded through the streets of London; they would never again field an army of comparable quality.
They also lost all their artillery and stores, along with Charles' personal baggage and private papers, which revealed his attempts to bring the Irish Catholic Confederation and foreign mercenaries into the war. These were published in a pamphlet titled The King's Cabinet Opened, whose appearance was a great boost to the cause of Parliament.
Background
In July 1644, a Parliamentarian force under Sir Thomas Fairfax and Oliver Cromwell secured control of Northern England by victory at Marston Moor. However, this was offset first by defeat at Lostwithiel in September, then lack of decisiveness at the Second Battle of Newbury in October. The two commanders involved, Essex and Manchester, were accused by many in Parliament of lacking commitment, a group that included moderates like Sir William Waller as well as radicals like Cromwell.
In December, Sir Henry Vane introduced the Self-denying Ordinance, requiring any military officers to resign from Parliament. As members of the House of Lords, Manchester and Essex were automatically removed since unlike MPs they could not resign their titles, although they could be re-appointed, 'if Parliament approved.' It also led to the creation of the New Model Army, a centralised, professional force. Moderates Fairfax and Philip Skippon were appointed Commander-in-Chief and head of the infantry respectively; Cromwell remained an MP but was given command of the cavalry on a 'temporary' three-month commission, constantly renewed.
At the outset of 1645, the Royalist high command was divided on strategy. Prince Rupert of the Rhine, recently appointed senior commander, wanted to link up with his brother Prince Maurice at Chester and retake the north, a key source of recruits and supplies. A faction headed by Lord Digby considered the New Model a threat to their capital at Oxford, while a third group preferred to consolidate control of the West Country. On 30 April, Fairfax marched west to relieve the Parliamentarian stronghold of Taunton; Lord Goring was despatched with 3,000 cavalry to support the Siege of Taunton, while the main Royalist field army of 8,600 men under Charles I and Prince Rupert moved north.
Concerned by this threat, Parliament's Committee of Both Kingdoms ordered Fairfax to change his plans and besiege Oxford. Although he made little progress, by the end of May the town was running short of provisions and to relieve the pressure, the Royalists stormed the Parliamentarian-held town of Leicester on 31 May, allegedly killing over 700 soldiers and civilians. Alarmed by this, Parliament instructed Fairfax to abandon the siege and on 5 June he marched north to engage the Royalist army. Unlike Prince Rupert who had been beaten by Fairfax and Cromwell the previous summer, Digby and Charles dismissed the fighting capabilities of the New Model. Despite being seriously outnumbered, they were eager for battle; messages were sent ordering Goring to rejoin them, but he refused to leave the West Country.
On 12 June, the Royalists were alerted to the presence of the New Model when Parliamentarian patrols clashed with their outposts near Daventry. The next day, Fairfax was reinforced by Cromwell's cavalry and troops from the Eastern Association under Edward Rossiter, bringing his numbers up to 14,000. Although Prince Rupert favoured withdrawing, Digby convinced Charles that retreat would be bad for morale and they decided to stand and fight.