York's little army marched down the Ermine Street; on May 20th he lay at Royston in Cambridgeshire. Beside the two Nevilles he had only one other peer in his company, Lord Clinton, and the knights present were merely the personal followers of York and Salisbury. Except a few of Warwick's Midland tenants, the whole army was composed of the Yorkshire retainers of York and Salisbury, and the chroniclers speak of the whole army as the Northern Men. More troops could have been had by waiting, but the Duke knew that if he delayed, the enemy would also gain time to muster in strength. At present the lords of the King's Council were quite unprepared for war, and the rapid march of York's little army had not allowed them time for preparation.
On the 21st the Duke felt his way southward along the line of the Ermine Street, and lay at Ware. There he and the two Earls indited a laborious apology for their arrival in arms to "their most redoubted sovereign Lord the King." They were "coming in grace, as true and humble liegemen, to declare and show at large their loyalty," and sought instant admission to the royal presence that they might convince him of the "sinister, malicious, and fraudulent reports of their enemies."
Somerset read clearly enough the meaning of York's march on London, and even before the Duke's manifesto was received, had stirred up the King to have recourse to arms. Many of the great lords of the King's party were in London, but they were surprised by the sudden approach of the enemy, and had brought few followers with them. Thus it came to pass that although the King marched out of Westminster on the 21st with many of the greatest lords of England at his back, he had less than three thousand combatants in his host. With him went forth his half-brother Jasper of Pembroke, the Dukes of Somerset and Buckingham, the Earls of Northumberland, Devon, Stafford, Wiltshire, and Dorset, and Lords Clifford, Dudley, Berners, and Roos, nearly a quarter of the scanty peerage of England. York's manifesto reached the King as he marched through Kilburn, but Somerset sent it back without allowing it to reach the royal hands. That night the army turned off the Roman road to shelter themselves in the houses of Watford; but next morning very early all were afoot again, and long before seven o'clock King Henry and his host reached St. Albans. The royal banner was pitched in St. Peter's Street, at the northern end of the straggling little town, the outlets of the streets were barricaded, and then the troops dispersed to water their horses and prepare breakfast. An hour later York and his forces appeared, advancing cautiously from the east along the Hertford Road. Hearing of the King's march on Watford, the Duke had left the direct line of advance on London, and set out to seek his enemies. When St. Albans was found to be strongly held, York, Salisbury, and Warwick drew up their four thousand men in battle array, in a field called Keyfield to the east of the town, and paused before attacking. They were hardly arrived before the Duke of Buckingham was seen emerging with a herald from the barricade which closed the eastern outlet of the town. This elderly nobleman was Salisbury's brother-in-law and Warwick's uncle; he was sure of a fair hearing from the insurgents, for he had never been identified with the party of Suffolk and Somerset, and was in arms out of pure loyalty to the King. Arrived in the presence of the rebel leaders, Humphrey of Buckingham demanded the cause of their coming and the nature of their intentions. The Duke of York replied by charging his master's envoy with a message for the royal ears, which began with all manner of earnest protestations of loyalty, proceeded with a vague declaration that the intent of his coming in arms was righteous and true, and ended with a peremptory demand that it would please the King "to deliver up such persons as he might accuse, to be dealt with like as they have deserved." Buckingham brought the message back and repeated it to the King, as he sat in the house of Westley, the Hundredman of the town of St. Albans, whither he had retired after his arrival. When the Duke's demand was made known, for once in his life the saintly King burst out into a fit of passion. "Now I shall know," he cried, "what traitors are so bold as to raise a host against me in my own land. And by the faith that I owe to St. Edward and the Crown of England, I will destroy them every mother's son, to have example to all traitors who make such rising of people against their King and Governour. And for a conclusion, say that rather than they shall have any lord here with me at this time, I will this day for his sake and in this quarrel stand myself to live or die."