House of Lancaster (The New Empire)

The House of Lancaster is the reigning royal house of the United Kingdom and the other Commonwealth realms. The first house was created when Henry III of England created the Earldom of Lancaster—from which the house was named—for his second son Edmund Crouchback in 1267. Edmund had already been created Earl of Leicester in 1265 and was granted the lands and privileges of Simon de Montfort, 6th Earl of Leicester, after de Montfort's death and attainder at the end of the Second Barons' War.

The house has been the Royal House of the United Kingdom since Henry IV in 1399. The current monarch King James III is the 30th monarch of the Lancaster house, thus giving the house the record for longest reigning Royal house surpassing 600 years in 1999 and the most monarchs in English or British history.