The House of Normandy, occasionally known as the House of Longsword, had Norwegian Viking roots and took the throne of England by conquest at the momentous Battle of Hastings in 1066, when they displaced the ancient line of native Saxon kings of the House of Wessex, which had ruled England since 827A.D.

The reign of William I, thereafter known as the Conqueror was stark and ruthless, a time of subjection for the English people.

The dynasty lasted for three generations, through the reigns of William's two sons, William II (1087-1100) and Henry I (1100-1135), both of whom were strong and efficient rulers, until civil war engulfed England as two of his grandchildren, Stephen (1135-54) (the son of the Conqueror's youngest daughter Adela) and Matilda (only legitimate daughter of his youngest son Henry I) became locked in a bitter struggle for the English crown. Leading to a Civil War which lasted for nineteen years, described by those who endured it as a time when "Christ and his saints slept". The dynasty of Norman kings ended on the death of King Stephen in 1154.