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. (May 2017)
The incapacitation of Henry VI by mental illness in 1454 had led to the recall to court of Richard of York, his closest adult relative. Back in 1447, York had been assigned as Lieutenant of Ireland, basically in exile away from England, while his long time rival, Edmund Beaufort, Duke of Somerset, and favorite of the king, had been given the charge of the Lieutenancy of France. After Somerset's own failure in France, York unexpectedly returned to London with significant support not only from the nobility, most of whom saw the incompetence of Somerset's efforts in France, but also from the public. He presented himself as a champion of the law and urged the King to have Somerset tried and held accountable for his failures. He also wished to be recognised as heir presumptive to the English throne while Henry VI was childless. York formed an armed force to force the issue in 1452, and after meeting with the council of war and the King, who desperately wanted to avoid a conflict, York's demands were agreed on. York disbanded his army as a result, but was soon arrested and held prisoner for three months. An execution was avoided as the King was nervous about arousing trouble; the Duke of York was very popular and known as a man of honour. York was only released after he agreed to swear an oath at St. Paul's Cathedral that he would never again take up arms against the King.
After the English army led by Sir John Talbot, 1st Earl of Shrewsbury, was routed in the Battle of Castillion, Henry VI suffered a complete mental breakdown and was unable to perform his royal duties. Somerset had attempted to take control of the country and sought to make himself Lord Protector. However, Somerset underestimated the Duke of York's influence and popularity, as many nobles on the council (including York's closest allies, his brother-in-law Richard Neville, Earl of Salisbury and Salisbury's son Richard, Earl of Warwick) were on York's side. And so York was given the appointment to govern England as Lord Protector and First Councillor of the realm while the king remained unfit. He used this position to move against his chief rival and express the bitterness which had accumulated over the years, and thus the Duke of Somerset was imprisoned. It was during this 14 months that the sides were clearly forming. There was conflict beyond that between the Dukes of York and Somerset; in fact, the two richest and most prominent families from the north, the Percys and Nevilles, were having their own conflicts. The Percys were, and still are to this day, the Earls of Northumberland; the Nevilles possessed both Salisbury and Warwick (received through the right of their wives) and they were one of the richest families in all England. The Nevilles were also related to the Duke of York by marriage, as the Duchess of York was Cecily Neville, the sister of the Earl of Salisbury. Much of the fighting was over land and money, but both were clearly choosing sides, the Percys for Somerset and the Nevilles for York.
By Christmas of 1454, King Henry had recovered from his illness, removing the basis for York's authority. Somerset was released and restored to his former position of power. Having reconvened the court at Westminster by mid-April 1455, Henry and a select council of nobles decided to hold a great council at Leicester. York and his closest allies anticipated that Somerset would bring charges against them at this assembly. They gathered an armed retinue and marched to stop the royal party from reaching Leicester, intercepting them at St Albans.