Rigby finally made up his mind to go to Bolton, thinking that Rupert would march either to Blackburn, or to Preston and Lancaster; but as it turned out the Parliamentarians only reached Bolton on the day before the royalists. Rigby occupied the town on May 27th, and next morning Rupert appeared before the town; and finding Rigby and his men in possession they determined on an assault. The chances were obviously in favour of the royalists. They were quite three to one in numbers, and were commanded by the dreaded Prince Rupert and by the Earl of Derby. Their opponents were disheartened by an unsuccessful three months' siege; moreover they were mostly newly raised troops, and as there had been no garrison kept in Bolton for almost twelve months the defences were considered out of repair. Nevertheless the fight was very fierce and for a time undecided. The royalists approached the town about 2 o'clock in the afternoon from the south-west, and at once delivered an attack at several quarters; but after about half an hour's hard fighting at close quarters the first assault was beaten off. The royalists state that they lost 200 men in this repulse. Colonel Rigby sent out of the town a troop of horse to stave off the second attack, but these were defeated. The Earl of Derby in person led the second attack, having requested Prince Rupert to allow him for this purpose two companies of his own soldiers then under the command of Colonel Tyldesley. After a quarter of an hour's desperate fighting the royalists effected an entrance, the Earl being the first man to enter. Some cavalry were admitted to another part of the town through the treachery of one of the townsmen, and caught between the two forces the Parliamentarian troops were routed. Each man saved himself as he might, but against the overwhelming superiority of the royalist horse in an unwalled town the defenders were helpless and the slaughter was great.[147] Little mercy was shown by the infuriated royalists, Prince Rupert having, on their own confession, at first forbidden quarter to be given to any in arms. Seacome states that 2,000 Parliamentarian soldiers out of a total of 3,000 were killed, and another royalist account puts the slain at 1,600 with 700 prisoners. Both these estimates are probably too high. It does not seem probable that Rigby had more than 2,500 men, and large numbers of these certainly escaped, while more than 200 were taken prisoners. A more reasonable estimate by a Parliamentarian writer places the total loss on both sides at 1,200 to 1,500, which is more likely to be correct. The Parliamentarians would not be likely to over-estimate their own losses. Of this 1,200 or 1,500 no doubt the larger number would belong to the town. Supposing the royalists to have lost 200 men in the first attack and 200 more during all the rest of the engagement, it would still make the losses of the town three or four times as numerous, which is credible enough; for the Parliamentarian