Royal badges had been around for many years as a sort of shorthand version of heraldry in comparison to a full-blown achievement of a Coat of Arms. Badges, because of their political symbolism, came into their heyday under the Tudors. However, Richard III fought under the Badge of a Blue Boar and Henry Tudor fought under the Badge of a Dragon. Although the Rose Badges did exist, the naming of the War of the Roses was retrospective and the juxtaposition of white rose versus red rose was Henry's invention.
The historian Thomas Penn writes in "How Henry VII branded the Tudors", The Guardian, 2 March 2012:
The "Lancastrian" red rose was an emblem that barely existed before Henry VII. Lancastrian kings used the rose sporadically, but when they did it was often gold rather than red; Henry VI, the king who presided over the country's descent into civil war, preferred his badge of the antelope. Contemporaries certainly did not refer to the traumatic civil conflict of the 15th century as the "Wars of the Roses". For the best part of a quarter-century, from 1461 to 1485, there was only one royal rose, and it was white: the badge of Edward IV. The roses were actually created after the war by Henry VII.
During his reign, Henry VIII had the legendary "Round Table" at Winchester Castle – then believed to be genuine – repainted. The new paint scheme included a Tudor Rose in the centre. This kind of use established Tudor Badges as a form of propaganda to define the Dynasty's claim to the throne.
The Tudor Rose badge may appear slipped and crowned, i.e. shown as a cutting with a stem and leaves beneath a Crown. The Badge appeared in this form in Nicholas Hilliard's "Pelican Portrait" of Elizabeth I and since an Order in Council (dated 5 November 1800), has served as the royal floral emblem of England as such.
The Tudor rose may also appear dimidiated (cut in half and combined with half of another emblem) to form a compound badge. The Westminster Tournament Roll includes a Badge of Henry and his first wife Catherine of Aragon with a slipped Tudor Rose conjoined with Catherine's personal Badge, the Pomegranate; their daughter Mary I bore the same Badge. Following his ascent to the English throne, James VI of Scotland and I of England used a badge consisting of a Tudor Rose dimidiated with a Scottish thistle and surmounted by a Royal Crown.
With the Union of England and Scotland into Great Britain in 1707 the joint Badge showed a full Tudor Rose and a full Thistle Head growing out of one stalk.
There have been many Badges over the years, starting with the punning Planta Genista or Broom Badge of the Plantagenet Dynasty.