As with many ancient breeds, tracing the Clumber's ancestry is a combination of research and guesswork. Its distinctive, massive head may be attributed to the early Alpine Spaniel, as well as its lemon and white coloring.

One theory surrounding Clumber origins begin in France, traced to the French Duc de Noailles from the Limousin area, south of Limoges, France. He had reportedly given (out of fear of his own life and those of his dogs at the time of the French Revolution (1789)) his entire kennel of prized spaniels to the 2nd Duke of Newcastle at Clumber Park in Nottingham, England. However, there seems to be no record of this anywhere in France or England. Aldred,"The Clumbers of Clumber Park" (1982), contacted the current Duc of Noailles whose family has no story of white Spaniels ("Clumber Spaniels" by Jan E. Irving)  so this could be romantic myth or folklore as well.

Until then, however, old land spaniels were called by various names: "cocker", "springers", "cock-flushers", to name a few, but the name "Clumber" undoubtedly arose from the Duke of Newcastle's estate at Clumber Park. The original stock was apparently given to Henry Clinton about 1768, when he inherited the estates and title from his uncle. There is a 1788 painting by F. Wheatley, "The Return from Shooting," showing the Duke with a number of white and lemon dogs, which are recognisable as forerunners of the modern Clumber. It is widely known that these dogs continued their association with the aristocratic houses of Great Britain, culminating with King Edward VII. King George V enjoyed using his Clumbers at Sandringham where he bred many working and show champions, the best remembered being Sandringham Spark.  It is often recorded that the Clumber Spaniel is believed to be one of the earliest spaniels developed for special uses.

The other theory surrounding the breed's origins lay in the old Blenheim of Woodcock Spaniel. A less popular theory - as it's less romantic - claims that the breed was developed by crossing large spaniels with St. Hubert 's hounds or Bassets. Although there is much circumstantial evidence to link the Clumber to this theory of development, one would never really be able to decide between which theory of development was correct, if either ? As the Clumber Spaniel differs so widely from other members of the spaniel group, his origin will probably always remain a mystery.  

The Duke of Newcastle's gamekeeper, William Mansell, during his 30 years of service to the Duke, is credited by many with developing and improving the breed. Although the Duke attempted to keep the breed to himself, the Clumber's popularity began to be appreciated by the middle of the 19th century. It was not uncommon in those days for the Duke to give Clumber pups as gifts to his friends.

In 1859, Clumbers were first shown in England. They have enjoyed considerable popularity in the U.K. In 1844, Lieutenant Venables, an officer of the British regiment stationed in Halifax, Nova Scotia, introduced the Clumber Spaniel to North America. The first Clumber Spaniel listed in the AKC registry, recorded for the date of 1878 was Bustler, an orange and white dog owned by Benjamin Smith of Nova Scotia. It is interesting to note that records of breedings of dogs in the United States existed long before the American Kennel Club was founded.  

While the Clumber was shown infrequently in American dog shows, interest in the breed throughout the years have maintained the breed's numbers. In the past century, more than 500 Clumbers have attained the title of Champion in the United States, with the majority of these achieved after 1968. In 1972, the Clumber Spaniel Club of America was founded with the purpose to protect and promote the integrity of the breed.