War of the Roses
The War of Roses was a series of on and off civil wars in the 1400's between the English royal houses of York and Lancaster.
The War of Roses got its name because the Lancaster King plucked a red rose from a nearby rosebush and the Duke of York plucked a white rose. The roses were then their symbols and therefor the wars were called "The Wars of the Roses."
Lancaster and York were fighting to see who would claim the throne because they were both decedents of Edward III. In the end Henry VII (from Lancaster) won. Henry Tudor married Elizabeth of York uniting the two houses.
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