The White Rose of York and the Red Rose of Lancaster were the emblems of the Royal Houses of York and Lancaster respectively, and first appeared on armoral bearings and standards during the Wars of the Roses 1450 - 1485. It was after the battle of Towton that Edward IV became the first Yorkist king, having two sons Edward and Richard and a daughter, Elizabeth. Upon Edward IV's early death, the eldest son Edward V became king, but before his Coronation he and his brother were murdered in the Tower of London. Richard Duke of Gloucester - brother of Edward IV - then took the throne becoming Richard III.
It was Richard's love of Yorkshire, spending much of his life in the county at Middleham Castle, that the White Rose emblem was also adopted for use as the county symbol and thus the Red Rose was associated to Lancashire.
After the defeat of Richard III at the Battle of Bosworth by Henry Tudor the Lancastrian heir to the throne, he was crowned Henry VII and married Elizabeth of York, the daughter of Edward IV and sister to the young princes who were murdered in the tower.
Thus ended the War of the Roses. The symbol for the new era was the Tudor Rose linking the White Rose of York with the Red Rose of Lancaster.

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