On 22 August 1485, Richard met the outnumbered forces of Henry Tudor at the Battle of Bosworth Field. Richard rode a white courser (an especially swift and strong horse).The size of Richard’s army has been estimated at 8,000 and Henry’s at 5,000, but exact numbers are not known, though the royal army is believed to have “substantially” outnumbered Henry’s. The traditional view of the king’s famous cries of “Treason!” before falling was that during the battle Richard was abandoned by Baron Stanley (made Earl of Derby in October), Sir William Stanley, and Henry Percy, 4th Earl of Northumberland.The role of Northumberland is unclear; his position was with the reserve—behind the king’s line—and he could not easily have moved forward without a general royal advance, which did not take place. The physical confines behind the crest of Ambion Hill, combined with a difficulty of communications, probably physically hampered any attempt he made to join the fray.Despite appearing “a pillar of the Ricardian regime” and his previous loyalty to Edward IV, Baron Stanley was the stepfather of Henry Tudor and Stanley’s inaction combined with his brother’s entering the battle on Tudor’s behalf was fundamental to Richard’s defeat. The death of Richard’s close companion John Howard, Duke of Norfolk, may have had a demoralising effect on the king and his men. Either way, Richard led a cavalry charge deep into the enemy ranks in an attempt to end the battle quickly by striking at Henry Tudor.