The opening of his campaign was indecisive, and it was not till fresh reinforcements arrived at Dublin that the king could prepare for a march into the heart of the island. But while he planned the conquest of Ireland the news came that England was lost. Little more than a month had passed after his departure when Henry of Lancaster entered the Humber and landed at Ravenspur. He came, he said, to claim his heritage; and three of his Yorkshire castles at once threw open their gates. The two great houses of the north joined him at once. Ralph Neville, the Earl of Westmoreland, had married his half-sister; the Percies came from their exile over the Scottish border. As he pushed quickly to the south all resistance broke down. The army which the Regent gathered refused to do hurt to the Duke; London called him to her gates; and the royal Council could only march hastily on Bristol in the hope of securing that port for the King's return. But the town at once yielded to Henry's summons, the Regent submitted to him, and with an army which grew at every step the Duke marched upon Cheshire, where Richard's adherents were gathering in arms to meet the king. Contrary winds had for a while kept Richard ignorant of his cousin's progress, and even when the news reached him he was in a web of treachery. The Duke of Albemarle, the son of the Regent Duke of York, was beside him, and at his persuasion the King abandoned his first purpose of returning at once, and sent the Earl of Salisbury to Conway while he himself waited to gather his army and fleet. The six days he proposed to gather them in became sixteen, and the delay proved fatal to his cause. As no news came of Richard the Welshmen who flocked to Salisbury's camp dispersed on Henry's advance to Chester. Henry was in fact master of the realm at the opening of August when Richard at last sailed from Waterford and landed at Milford Haven. [Sidenote: Richard's capture]