Which preposition to use with yorkists

at Occurrences 2%

He feigned a retreat, and allured Audley to follow him with precipitation; but when the van of the royal army had passed the brook, Salisbury suddenly turned upon them, and partly by the surprise, partly by the division of the enemy's forces, put this body to rout; the example of flight was followed by the rest of the army; and Salisbury, obtaining a complete victory, reached the general rendezvous of the Yorkists at Ludlow.

in Occurrences 2%

Richard was the son of Richard, Duke of York, and Cecily Neville, daughter of the Earl of Westmoreland, his father being the legitimate heir to the throne by descent in the female line, so he was the head of the Yorkists in the War of the Roses.

on Occurrences 1%

NORTHAMPTON (70), capital of Northamptonshire, on the Nen, 66 m. NW. of London; has two fine old Norman churches, is the centre of the boot and shoe manufacture, and is actively engaged in brewing, lace-making, &c.; in the outskirts is a popular racecourse; was the scene of Henry VI.'s defeat by the Yorkists on July 10, 1460.

under Occurrences 1%

TEWKESBURY (5), a market-town of Gloucestershire, at the confluence of the Avon and Severn (here spanned by one of Telford's bridges), 10 m. NE. of Gloucester; possesses one of the finest of old English churches in the Norman style; trades chiefly in agricultural produce; half a mile distant is the field of the battle of Tewkesbury (May 4, 1471), where the Yorkists under Edward IV.

Which preposition to use with  yorkists