William II de Ferrers, 4th Earl of Derby (c. 1168 – c. 1247) was a favourite

Favourite

A favourite , or favorite , was the intimate companion of a ruler or other important person. In medieval and Early Modern Europe, among other times and places, the term is used of individuals delegated significant political power by a ruler...

 of King John of England

John of England

John , also known as John Lackland , was King of England from 6 April 1199 until his death...

. He succeeded to the estate (but not the title) upon the death of his father, William de Ferrers, 3rd Earl of Derby

William de Ferrers, 3rd Earl of Derby

William I de Ferrers, 3rd Earl of Derby was a 12th century English Earl who resided in Tutbury Castle in Staffordshire and was head of a family which controlled a large part of Derbyshire known as Duffield Frith. He was also a Knight Templar....

, at the Siege of Acre in 1190. He was head of a family which controlled a large part of Derbyshire

Derbyshire

Derbyshire is a county in the East Midlands of England. A substantial portion of the Peak District National Park lies within Derbyshire. The northern part of Derbyshire overlaps with the Pennines, a famous chain of hills and mountains. The county contains within its boundary of approx...

 which included an area known as Duffield Frith

Duffield Frith

Duffield Frith was, in medieval times, an area of Derbyshire in England, part of that bestowed upon Henry de Ferrers by King William, controlled from his seat at Duffield Castle. From 1266 it became part of the Duchy of Lancaster and from 1285 it was a Royal Forest with its own Forest Courts.It...

.

He adopted his father's allegiance to King Richard

Richard I of England

Richard I was King of England from 6 July 1189 until his death. He also ruled as Duke of Normandy, Duke of Aquitaine, Duke of Gascony, Lord of Cyprus, Count of Anjou, Count of Maine, Count of Nantes, and Overlord of Brittany at various times during the same period...

 as the reigning king. On Richard's return from the Third Crusade

Third Crusade

The Third Crusade , also known as the Kings' Crusade, was an attempt by European leaders to reconquer the Holy Land from Saladin...

, in the company of David Ceannmhor and the Earl of Chester

Earl of Chester

The Earldom of Chester was one of the most powerful earldoms in medieval England. Since 1301 the title has generally been granted to heirs-apparent to the English throne, and from the late 14th century it has been given only in conjunction with that of Prince of Wales.- Honour of Chester :The...

 he played a leading role in besieging Nottingham Castle

Nottingham Castle

Nottingham Castle is a castle in Nottingham, England. It is located in a commanding position on a natural promontory known as "'Castle Rock'", with cliffs high to the south and west. In the Middle Ages it was a major royal fortress and occasional royal residence...

, on the 28th March 1194, which was being held by supporters of Prince John.