One inquiring mind asked, “Why do we have gray Thoroughbreds, and where do they come from?” Who can resist such a question?

The first part is fairly easy. Gray Thoroughbreds are part of the breed because they have been here from the beginning, and the coat color is with us today because a gray parent will give its graying color factor to approximately half of his offspring, and those gray offspring will pass it on through time.

Surprisingly enough, at least to me, is the fact that gray nearly died out. Went very quiet, both here and overseas. Through much of the 19th century, it was not common to see a gray, nor especially a top-quality horse of that color.

Today, much of the color comes from multiple leading sire Tapit, as well as from Unbridled’s Song. The latter gets his gray from his broodmare sire Caro, and more on that in a minute. Tapit’s gray comes through his fourth dam and three subsequent gray mares, but fourth dam Foggy Note (by The Axe) presents us with the first part of a significant question.

The problem with Foggy Note is that both her parents are gray!

Since we can’t know specifically which graying factor came forward to Tapit, The Axe (by the gray English Derby winner Mahmoud) and Silver Song (by the bay Royal Note) present the first quandary in tracing the gray lineage that we see from Tapit today. Or so it appears.

The gray factor through The Axe and Mahmoud comes from the latter’s dam, Mah Mahal, a daughter of Gainsborough and the great gray racer Mumtaz Mahal. An even better race filly than anything she produced, Mumtaz Mahal was quite a good broodmare and a great producer of producers. Her daughters are responsible not only for leading sire Mahmoud but also Nasrullah, and Mumtaz Mahal is the third dam of leading sire Royal Charger, as well as Arc de Triomphe winner Migoli (Bois Roussel), who is the sire of Belmont Stakes winner Gallant Man.

Mumtaz Mahal got the gray from her sire The Tetrarch (Roi Herode).

Where then does the gray come from on the other side of Foggy Note’s pedigree? It goes back through a line of gray mares to Tapit’s ninth dam Silver Beauty, who is a daughter of the gray Stefan the Great, a son of The Tetrarch who won the Middle Park Stakes at two in 1918 and was imported to the States. All nine of the gray dams leading to Tapit are bred in the States and represent the longest sequence of same-sex graying that I have encountered.

So, although Foggy Note presents us with a problem of her two gray parents, we can resolve it because both graying factors came from the same stallion The Tetrarch.

In the case of Unbridled’s Song, whose gray comes through his broodmare sire Caro, the gray factor goes back another seven generations to its source, The Tetrarch.

The unbeaten gray son of Roi Herode is thus the source of nearly all the gray in the breed.

The Tetrarch’s sire was bred in France by Maurice Caillaut and was a high-class racehorse whose best form came as a front-running stayer, but in the best races, there was always one who could catch him in the stretch, and Roi Herode was second in his most important French races, the Prix du President de la Republique and Prix Royal Oak, as well as in the Doncaster Cup. The horse was purchased by Edward Kennedy for 2,000 pounds after finishing second at Doncaster but bowed a tendon the following season when in training and went to stud at Kennedy’s Straffan Stud in County Kildare, where he sired The Tetrarch in his first crop.

Roi Herode’s sire Le Samaritain and grandsire Le Sancy were both bred in France by Arthur de Schickler, who raced them successfully. Le Samaritain was a good racehorse, but Le Sancy was somewhat better, both on the racecourse and at stud. An immensely tough racehorse, Le Sancy won 27 of his 43 starts, had speed, and stayed well.

Good as he was on the racecourse, Le Sancy became a sire out of all proportion to his racing class, siring top juveniles like Le Sagittaire (Prix Morny, Grand Criterium), 3-year-olds who won classics at 3 like Ex Voto (Prix du Jockey Club), and others that trained on to excel as older horses like Le Justicier (Eclipse Stakes). The best of Le Sancy’s many good horses was Semendria, a gray filly who won the 1900 Poule d’Essai des Pouliches, Prix Vermeille, and Grand Prix de Paris, when the latter was the most important all-age contest in Europe.

Le Sancy and his successors at stud also breathed life back into the floundering male line of the Byerley Turk through Herod, and Kennedy, who was a fancier of this male line, was partly attracted to Roi Herode because his name is the French for King Herod.

From Le Sancy, the graying factor goes back through his dam Gem of Gems, through her sire Strathconan, his dam Souvenir, and then to Chanticleer. An appropriately named son of Birdcatcher, Chanticleer got his gray coat from his dam Whim, and the gray factor then goes through her sire Drone and grandsire Master Robert to the latter’s dam Spinster, a foal of 1803.

Spinster begins a series of seven gray mares, the second-longest same-sex series in the line, to a daughter of the gray stallion Crab (Alcock Arabian). But, as might happen, there is a second puzzle in this line of grays. Spinster’s second dam is Bab, and both her parents are gray.

Bab’s sire is the gray horse Bourdeaux (Herod 1758), and her dam is the gray mare Speranza (Eclipse 1764). Yes, that Herod and that Eclipse, neither of whom was a gray. But the mares they were bred to were grays and passed on the coat color to the next generation.

In the fifth generation of Bab’s pedigree, Crab is the sire of her fourth dam, a gray mare of 1750. In the top half of Bab’s pedigree, Crab occupies the same generation but is the broodmare sire of the broodmare sire of Bourdeaux. So it appears that all grays lead back to Crab and the Alcock Arabian.

But this is a relatively old piece of Thoroughbred pedigree recording, and things are never as simple as we might hope.

Before we quite get back to Crab, Bourdeaux’s broodmare sire is Cygnet, a gray son of the Godolphin Arabian (1724-ish), and out of Godolphin Blossom, both of whose parents are gray. Her sire Crab is a known quantity for the gray team, but her dam is a gray Flying Childers mare whose gray factor may have come from the Brownlow Turk, a more mysterious horse born around 1695.

So there is a possibility that the gray coat found in racehorses comes from a horse about whom we know almost nothing, but that’s only a 50-50 chance, and after all, it’s not the coat that counts, it’s what’s inside.