Rupert Matthews, historian and author writes at historyextra.com:
“The Wars of the Roses were the civil wars fought in England and Wales between the Yorkist and Lancastrian dynasties between 1455 and 1485, with some related battles fought both before and after the main period of conflict.
At the time of the conflict, the various contingents fought under the heraldic banner of their lord. However, after his coronation the Lancastrian Henry VII married Elizabeth of York and adopted as a badge the bicoloured Tudor Rose. This blended the red rose of Lancaster and the white rose of York, neither of which had been an important badge until this time.
The rose symbols were first brought to prominence by William Shakespeare in his play *Henry VI part 1. Shakespeare invented a scene set in the gardens of the Temple Church (see view of interior above) in London in which the noblemen pick a red or a white rose to signify whom they support.
However, it was not until the later 18th century that historians began to acknowledge the symbolic reconciliation of the Tudor Rose. That in turn caused Sir Walter Scott to refer to the conflict as “The Wars of the Roses” in his historical novel Anne of Geierstein (1829). Thereafter the term entered widespread use among historians and the general public.”