Civil War in Yorkshire, 1642
By March 1642, the quarrel between King Charles I and the Long Parliament had escalated to the extent that the King left the vicinity of London and travelled north. He established his court at York, which became the de facto capital of England, and set about consolidating support amongst his northern subjects.
The First Siege of Hull, July 1642

In April, the King moved to secure the town of Hull — a major port with trading links to Europe and the site of an arsenal of weapons stored after the recent wars against Scotland. King Charles was also anxious to secure a safe landing place for Queen Henrietta Maria, who had left England the previous month to raise money and munitions from Europe in preparation for the struggle against Parliament. But Parliament had taken precautions to secure Hull for itself by appointing Sir John Hotham as governor and issuing instructions that the town and its arsenal were not to be surrendered without parliamentary authority. Consequently, when Charles arrived with his entourage before Hull on 23 April 1642, he found the town gates barred against him. After several hours' fruitless negotiation between the royal heralds, Hotham and the aldermen of Hull, King Charles rode away to York. The following day, he pronounced Sir John Hotham guilty of high treason.
In June, Charles sent William Cavendish, Earl (later Marquis) of Newcastle, to secure the city of Newcastle, its adjacent ports and the Northumberland and Durham coalfields. Then, with a force of 3,000 foot and 1,000 horse, the King returned to Hull early in July 1642, setting up his court at Beverley and quartering his forces around the village of Anlaby. Parliament had ordered the removal of most of the weapons and ammunition from the northern arsenal to London, but enough was left for the town's defence; the citizens of Hull had also strengthened its defences with new earthworks, and on 6 July, the sluices were opened and the banks of the River Humber broken to flood the land for two miles around the town. On 10 July, a Royalist raiding party approached Hull to intimidate the defenders by burning down buildings outside the town walls. In the first military action of the English Civil War, the Royalists were driven away by gunfire from the defenders of Hull.
Following an appeal to Parliament, Sir John Meldrum arrived by sea with 1,500 troops to direct Hull's defence. The flooding of the surrounding land made it difficult for the Royalists to set up artillery positions, but several strong-points were established around the western approaches to the town. Utilising the defenders' local knowledge, however, Meldrum directed attacks on the Royalist positions, culminating in a night raid on Royalist headquarters at Anlaby with the attackers approaching by raft across the flooded land. The Royalists were taken by surprise and routed; the Parliamentarians captured several artillery pieces. Discouraged by the vigour of the Parliamentarian defence, King Charles abandoned the siege of Hull at the end of July and withdrew to York.
Tadcaster and Bradford, December 1642
In August, King Charles appointed the Earl of Cumberland lord-lieutenant of Yorkshire and commander of Royalist forces in the region. The King then marched south to marshall his forces at Nottingham. Lord Cumberland proved to be an ineffective commander and the Yorkshire Parliamentarians were able to raid Royalist positions at will from their strongholds at Selby, Hull, Scarborough and the West Riding cloth towns. In October 1642, the Yorkshire Royalists appealed to the Earl of Newcastle for help. Having secured Royalist control of the northern counties of Northumberland, Durham, Westmoreland and Cumberland, Newcastle marched south into Yorkshire with a force of 6,000 foot and 2,000 horse and dragoons in December 1642. Captain Hotham attempted to prevent the Royalists from crossing the River Tees at Piercebridge, but with only three troops of horse and four companies of foot against Newcastle's army, Hotham was easily driven back. On 3 December 1642, the Royalists marched unopposed into York.

Parliament's leading commander in the north was Lord Fairfax, who was proclaimed leader of the Yorkshire Parliamentarians in September 1642. After local militia and irregular "clubmen" succeeded in beating off a Royalist attempt to seize Bradford in October, Fairfax set about recruiting and training an army in the area. At the end of November, he occupied Tadcaster with 900 men, while his son Sir Thomas Fairfax occupied Wetherby with 300 foot and about 40 horse. Although the Fairfaxes controlled important crossings over the River Wharfe and seemed in a strong position to threaten York, they were greatly outnumbered by the Earl of Newcastle's army. On 6 December, Newcastle attacked Tadcaster. Short of ammunition and outnumbered, Lord Fairfax was unable to hold the town and fell back to Selby the following day. Newcastle moved on to capture Pontefract, thus cutting off the Parliamentarian towns in the West Riding of Yorkshire from the strongholds of Selby and Hull. A Royalist cavalry detachment commanded by Sir John Henderson swept south through Nottinghamshire and secured Newark, which remained an important Royalist garrison throughout the First Civil War.
As the Earl of Newcastle advanced south, the Royalist Sir William Savile seized the West Riding towns of Leeds and Wakefield without opposition. However, Savile met with resistance when he attempted to storm Bradford on 18 December. Reinforced by volunteers from the surrounding region, the citizens of Bradford drove back the Royalists and forced Savile to retreat to Leeds. Although Bradford was unfortified and of little strategic value, it became a focal point for Parliamentarian support in the West Riding. Sir Thomas Fairfax made a daring night march through Royalist-held territory with a detachment from Selby to reinforce Bradford on 23 December 1642.
Sources:
A.H. Burne & P. Young, The Great Civil War, a military history (London 1958)
S.R. Gardiner, History of the Great Civil War vol. i (London 1888)
P.R. Newman, Atlas of the English Civil War (London 1985)
C.V. Wedgwood, The King's War (London 1958)