Discuss the roles of the Yorkists and Lancastrians during the Wars of the Roses.

The Yorkists and Lancastrians were the two rival factions that fought for control of the English throne during the Wars of the Roses.

The Wars of the Roses, a series of civil wars in England from 1455 to 1487, were primarily a power struggle between two branches of the Plantagenet family: the House of York, symbolised by a white rose, and the House of Lancaster, represented by a red rose. These two factions, the Yorkists and Lancastrians, played pivotal roles in this tumultuous period of English history.

The Yorkists, led by Richard, Duke of York, and later by his sons Edward IV and Richard III, were initially the challengers to the throne. They claimed a superior line of descent from Edward III, which they argued gave them a stronger claim to the throne than the reigning Lancastrian king, Henry VI. The Yorkists were largely supported by the nobility of northern and eastern England, as well as by some important figures in the south. Their power base was further strengthened by Edward IV's marriage to Elizabeth Woodville, which brought the support of her extensive family and connections.

The Lancastrians, on the other hand, were the defenders of the status quo. They were led by Henry VI and, after his death, by his wife Margaret of Anjou and their son Edward, Prince of Wales. The Lancastrians drew their support primarily from the nobility of southern and western England. They were also backed by the House of Tudor, through Margaret of Anjou's marriage to Henry VI. Despite Henry VI's weak leadership and bouts of mental illness, the Lancastrians were able to maintain their hold on the throne for much of the conflict due to their strong alliances and the loyalty of their supporters.

The roles of the Yorkists and Lancastrians during the Wars of the Roses were not static, however. As the conflict progressed, alliances shifted, leaders changed, and the balance of power swung back and forth. The Yorkists, for example, were briefly ousted from power during the 'Readeption of Henry VI', only to regain the throne with the victory of Edward IV at the Battle of Tewkesbury. The Lancastrians, meanwhile, were ultimately able to secure the throne with the victory of Henry Tudor (a distant Lancastrian claimant) at the Battle of Bosworth Field, marking the end of the Wars of the Roses and the beginning of the Tudor