Lancashire is a in the North West of England, bounded to the west by the Irish Sea. It takes its name from the city of Lancaster. The Red Rose of Lancaster is the traditional symbol for the House of Lancaster.
In the Domesday Book, most of Lancashire was treated as part of Yorkshire. The area in between the Mersey and Ribble or "Inter Ripam et Mersham" formed part of the returns for Cheshire. Lancashire is named from the city of Lancaster, which itself is derived from the River Lune, was established some time after the Norman conquest when William the Conqueror gave the land between the river Ribble and the Mersey to Roger de Pitou. In the early 1090s Lonsdale, Cartmel and Furness were added to Roger's estates to facilitate the defence of the area south of Morecambe Bay from Scottish raiding parties, which travelled round the Cumberland coast and across the bay at low water, rather than through the mountainous regions of the Lake District.
The county was divided into the six hundreds of Amounderness, Blackburn, Leyland, Lonsdale, Salford and West Derby. Lonsdale was further partitioned into Lonsdale North, which was the detached part north of Morecambe Bay also known as Furness, and Lonsdale South.
The Red Rose of Lancaster is the traditional symbol for the House of Lancaster, immortalized in the verse "In the battle for England's head - York was white, Lancaster red", referring to the 15th century War of the Roses. The House of Lancaster was a branch of the English royal House of Plantagenet. It was one of the opposing factions involved in the Wars of the Roses, an intermittent civil war which affected England and Wales during the 15th century. The House is named Lancaster, because its members were all descended from Edward III's son John of Gaunt, 1st Duke of Lancaster. The opponents of the House of Lancaster were the House of York. The rivalry between Lancaster and York, in the form of the counties of Lancashire and Yorkshire, has continued into the present day, on a more friendly basis, the annual sporting competition between Lancaster University and the University of York is called the Roses Tournament.
The end of the House of Lancaster occurred at the Battle of Tewkesbury in 1471. However, the House of Tudor, which ruled England from 1485 to 1603, was descended from the Lancasters by way of Margaret Beaufort, great granddaughter of John of Gaunt, who married Edmund Tudor, Earl of Richmond, and was the mother of Henry VII of England. Henry VII cemented his claim to the throne by marrying Elizabeth of York the heir to the Yorkist line. Their children and grandchildren became the House of Tudor and their great grandson was the first king of England belonging to the House of Stuart, King James VI of Scotland.