Short answers, pulled from the story.
Henry VII created the Tudor rose immediately after the Battle of Bosworth Field on the 22nd of August 1485. This artificial flower served as a calculated political invention to merge the warring factions of the House of Lancaster and the House of York.
The design features five white inner petals representing the House of York and five red outer petals representing the House of Lancaster. This double rose was heraldically described as proper to symbolize the union of the two houses.
The symbol became the standard for the royal floral emblem of England following an Order in Council dated the 5th of November 1800. This iteration appeared as a cutting with a stem and leaves beneath a crown in the Pelican Portrait of Elizabeth I.
The crowned and slipped Tudor rose features in the design of the 20-pence coin minted between 1982 and 2008. It also appears in the royal coat of arms of the United Kingdom and the coat of arms of Canada.
The symbol appears on the dress uniforms of the Yeomen Warders at the Tower of London and the Yeomen of the Guard. It also serves as the emblem of The Nautical Training Corps and makes up part of the cap badge of the Intelligence Corps of the British Army.
The borough and county of Queens in New York City uses a Tudor rose on its flag and seal. The flag and seal of Annapolis, Maryland, features a Tudor rose and a thistle surmounted with a crown, while York, South Carolina and Lancaster, South Carolina use stylized white and red roses in their emblems.