One of the most influential imported eastern stallions, he was probably of equal importance to the establishment of the stud book as were the Byerley Turk, the Darley Arabian, and the Godolphin Arabian. William Pick noted that his celebrity was such that he was referred to simply as the Bay Barb, as if no other barb of that colour had ever stood in England. Cheny (1747) wrote that the Bay Barb and the Thoulouse Barb were imported by Henry Curwen. "That Gentleman being in France at a time when Count Byram and Count Thoulouse (two natural Sons of Lewis the Fourteenth) were, the former, Master of the Horse, and the other an Admiral, he procured of them two Barb Horses, which he convey'd to England."

Louis XIV had a number of illegitimate children, including Louis Alexandre, Comte de Toulouse, who at one time did hold the rank of admiral. But no trace can be found of a son titled Count Byram, much less one who was master of the horse (called in France “Grand Écuyer” or simply “Monsieur le grand”). From 1677 to 1712, the Grand Écuyer was Henri de Lorraine, Comte de Brionne – a name which, by eighteenth-century spelling standards, is quite similar to Byram. Although Brionne was not a son of the king, he was indeed a count and, even more significantly, he was master of the horse. It is almost certain that, by virtue of his office, Brionne’s knowledge and cooperation would have been required for the removal of any horses from the French royal stud. One theorist therefore hypothesizes that English writers such as Cheny (who was based in Yorkshire) accidentally substituted Byram, a name with which they were naturally more familiar, for Brionne.

Another theorist believes that Byram is truly the correct spelling and proposes the following scenario … According to J B Robertson ("Mankato"), Henry Curwen was one of the followers of King James II who accompanied him when he fled to France in 1688 [Robertson:33], where he remained until around 1698. It seems likely that Curwen purchased the Bay Barb after his arrival in France and had him sent to England around 1689. Highflyer speculates that since a diligant search unearthed no such person as Count of Byram, allegedly a son of the French king, that the Byram in question may have been Sir William Ramsden (1672-1736), 2nd Baronet of Byram, near Ferrybridge, Yorkshire.

Mr Prior notes that "Sir William [Ramsden] married a daughter of John Lowther (1655-1700), 1st Viscount Lonsdale, who himself lived some time at Byram, and no doubt brought the Eastern-bred mares with him from Lowther" [Early Records:125]. The Thoulouse Barb, also purchased by Mr Curwen, may have travelled with the Barb on his trip to Curwen's stud at Workington Hall, near Whitehaven in Cumberland. Curwen's Bay Barb is sometimes referred to by the General Stud Book as the "Curwen or Pelham Bay Barb". Charles Pelham, an associate of Curwen's, may have stood the Barb at his Brocklesby Park stud in Lincolnshire since Curwen, a Roman Catholic, was subject to the law that forbade Catholics to own horses valued at more than £5.

In any case he first made his mark as a stallion based on the turf achievements of his offspring. The stud book makes note of his runners, mentioning the Mixbury Galloway and Tantivy, said to be very high-formed galloways. Brocklesby and Little George were said to be in good forms, and Yellow Jack, Bay Jack, Monkey, Dangerfield, Hip, Peacock and Flatface in middling forms. Two brothers to Mixbury were described as middling galloways, presumably distinguished by their small size. The mares Long Meg, Brocklesby Betty and Creeping Molly were noted as extraordinary high-formed mares, while Whiteneck, Mistake, Sparkler and Lightfoot were said to be very good mares. Not all of these runners left stock that bred on, and some of his best breeding stock never saw a racecourse.

In the stud his sons were less noteworthy than his daughters, with Hip (gr c 1716) probably the best of them. Although at the time Brocklesby Betty was probably the most famous of his daughters, eventually Sister 1 to Mixbury was probably the most influential, via her famous son Partner, sire of numerous excellent daughters and grandsire of King Herod.

Curwen's Bay Barb was said to have lived to the remarkable age of thirty-eight, and to have stood for his portrait at the age of twelve. Although Henry Curwen died in 1725, and made provisions in his will for a number of his broodmares, no mention was made of the Barb [ER:146]. He probably died at Brocklesby Park around 1719.