The Wars of the Roses were a series of dynastic wars for the throne of England. They were fought between supporters of two rival branches of the royal House of Plantagenet, the houses of Lancaster and York. They were fought in several sporadic episodes between 1455 and 1487, although there was related fighting before and after this period. The conflict resulted from social and financial troubles that followed the Hundred Years' War, combined with the mental infirmity and weak rule of Henry VI, which revived interest in the alternative claim to the throne of Richard, Duke of York.
The final victory went to a claimant of the Lancastrian party, Henry Tudor, who defeated the last Yorkist king, Richard III, at the Battle of Bosworth Field. After assuming the throne as Henry VII, Henry Tudor married Elizabeth of York, the eldest daughter and heiress of Edward IV, thereby uniting the two claims. The House of Tudor ruled England and Wales until 1603.
The Battle of Bosworth (or Bosworth Field) was the last significant battle of the Wars of the Roses, the civil war between the Houses of Lancaster and York that raged across England in the latter half of the 15th century. Fought on 22 August 1485, the battle was won by the Lancastrians. Their leader Henry Tudor, Earl of Richmond, by his victory became the first English monarch of the Tudor dynasty. His opponent, Richard III, the last king of the House of York, was killed in the battle. Historians consider Bosworth Field to mark the end of the Plantagenet dynasty, making it a defining moment of English and Welsh history.
Richard's most loyal subject was John Howard, 1st Duke of Norfolk. The duke had served Richard's brother for many years and was one of Edward IV's closer confidantes, he was a military veteran, having fought in the Battle of Towton in 1461 and served as Hastings' deputy at Calais in 1471.
Richard formed his army into three divisions or ‘battles”, The Vanguard or main "battle” was under the command of the Duke of Norfolk, the main body was led by Richard, and the rearguard under the command of the Earl of Northumberland
Henry recruited several experienced veterans on whom he could rely for military advice and the command of his armies, most notably John de Vere, 13th Earl of Oxford, who was Henry's principal military commander.
Henry Tudor decided to commit most of his small force into one single large division or "battle” and place it under the command of the Earl of Oxford.