Family Numbers
Today most thoroughbreds from all countries belong to English families whose foundation or taproot mares are recorded in the General Stud Book of the United Kingdom. However, there are families that can be traced only as far as existing records permit. For example, in America, records were lost during the American Revolutiony War (1775-1783) and the Civil War (1861-1865) leaving the history of some families incomplete and without connection to the General Stud Book, and these families are now classified as American families.

English families were of sufficient size to require further subdivision and these are shown as Family 1-a, 1-b, etc. Well populated families will have divisions as recent as the twentieth century, such as that of Family 14-c, headed by Pretty Polly who was foaled in 1901 and La Troienne who was foaled in 1926.

Early family tables incorporate recent research and the corrections are discussed at the bottom of such pages. While none of the tables is meant to be comprehensive, we are adding classics winners.

English Families

English Families lists the traditional taproot mares from 1 to 74, plus some families we've recently numbered. (You can also click on the button). You can go directly to the table for a specific family using the numbers below. The Summary of Corrections lists some of the known errors that have been corrected by later researchers. The letters "q" and "v" were not used by Bobinski and Zamoyski in their Family Tables of Racehorses. The taproot mare of Family 15-c, Selima, was later assigned to Family 21. The taproot mare of Family 50, Miss Euston, was re-assigned to Family 13.

1 1a 1b 1c 1d 1e 1f 1g 1h 1i 1j 1k 1l 1m 1n 1o 1p 1q 1r 1s 1t 1u 1v 1w 2 2a 2b 2c 2d 2e 2f 2g 2h 2i 2j 2k 2l 2m 2n 2o 2p 2q 2r 2s 2t 2u 2v 2w 3 3a 3b 3c 3d 3e 3f 3g 3h 3i 3j 3k 3l 3m 3n 3o 4 4a 4b 4c 4d 4e 4f 4g 4h 4i 4j 4k 4l 4m 4n 4o 4p 4q 4r 5 5a 5b 5c 5d 5e 5f 5g 5h 5i 5j 6 6a 6b 6c 6d 6e 6f 6x 7 7a 7b 7c 7d 7e 7f 8 8a 8b 8c 8d 8e 8f 8g 8h 8i 8j 8k 9 9a 9b 9c 9d 9e 9f 9g 9h 10 10a 10b 10c 10d 10e 11 11a 11b 11c 11d 11e 11f 11g 12 12a 12b 12c 12d 12e 12f 12g 13 13a 13b 13c 13d 13e 14 14a 14b 14c 14d 14e 14f 15 15a 15b 15c 15d 16 16a 16b 16c 16d 16e 16f 16g 16h 17 17a 17b 17c 17d 18 18a 19 19a 19b 19c 20 20a 20b 20c 20d 21 21a 22 22a 22b 22c 22d 23 23a 23b 24 25 26 27 27a 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74

Family 1-x, belonging to La Troienne*, was numbered by Janeen Oliver on her Mare Maps, copyrighted in 2000 and displayed in 2002 at the TIEC trade show in Lexington, and implemented by the Pedigree Online Thoroughbred Database (formerly Del Mar Pedigree Query) in 2003. You are welcome to use the number if you wish. 1x

Family 6-x is a temporary classification for the descendants of Milbanke's Bald Peg. 6x

Selima was traditionally assigned to Family 15-c, however, C M Prior discovered her true pedigree which indicated that she belonged to Family 21. Her offspring are sufficiently numerous that we have given her a page of her own, although she remains part of Family 21. Selima*

The following families were initially assigned to traditional families, however, there is some doubt about the authenticity of their pedigrees, hence they have been alloted their own pages.
Jenny Cameron*, Kitty Fisher*, Mary Grey*

The following families have been numbered by us for research purposes. You are welcome to use the numbers if you wish. The tables are presently under construction.
100 101 102 103 104

American Families
American Families lists the taproot mares of North America from A1 to a90. (You can also click on the button). You can go directly to a specific family by clicking on the number below. The tables are presently under construction. For more information on the recently classified American families a40 to a90 see Foundation Matriarchs of the Thoroughbred. There are also a few Appendix families, or mare lines with short pedigrees. You are welcome to use these numbers if you wish. Please address questions or comments regarding American Families to Christine Matthes.
A1 A2 A3 A4 A5 A6 A7 A8 A9 A10 A11 A12 A13 A14 A15 A16 A17 A18 A19 A20 A21 A22 A23 A24 A25 A26 A27 A28 A29 A30 A31 A32 A33 A34 A35 A36 A37 A38 A39 a40 a41 a42 a43 a44 a45 a46 a47 a48 a49 a50 a51 a52 a53 a54 a55 a56 a57 a58 a59 a60 a61 a62 a63 a64 a65 a66 a67 a68 a69 a70 a71 a72 a73 a74 a75 a76 a77 a78 a79 a80 a81 a82 a83 a84 a85 a86 a87 a88 a89 a90

Appendix Families
Colonial Families
Colonial Families lists the taproot mares of Australia and New Zealand from C1 to c72. (You can also click on the button). You can go directly to a specific family by clicking on the number below. Families numbered from c36 to c72 have recently been numbered for research purposes. You are welcome to use these numbers if you wish. The tables are presently under construction. Please address comments or questions regarding Colonial Families to Carole Goodwin.
C1 C2 C3 C4 C5 C6 C7 C8 C9 C10 C11 C12 C13 C14 C15 C16 C17 C18 C19 C20 C21 C22 C23 C24 C25 C26 C27 C28 C29 C30 C31 C32 C33 C34 C35 c36 c37 c38 c39 c40 c41 c42 c43 c44 c45 c46 c47 c48 c49 c50 c51 c52 c53 c54 c55 c56 c57 c58 c59 c60 c61 c62 c63 c64 c65 c66 c67 c68 c69 c70 c71 c72 c73 c74
Half-Bred Families
Half-bred Families - lists those English families from B1 to B26 whose foundation mares were not recorded in the General Stud Book. (You can also click on the button). You can go directly to a specific family by clicking on the number below.
B1 B2 B3 B4 B5 B6 B7 B8 B9 B10 B11 B12 B13 B14 B15 B16 B17 B18 B19 B20 B21 B22 B23 B24 B25 B26
Other Families
Other Families - lists the taproot mares of Argentina, Poland and Uruguay. (You can also click on the button). You can go directly to a specific family by clicking on the number below. An Uraguayan family was identified by Gustavo Mèndez and Tom Viebke in 2001.
Ar1 Ar2 P1 P2 Ur1
History of Family Numbers and Tables

Toward the end of the 19th century Bruce Lowe and others made attempts to classify the foundation, or taproot, mares according to the success, on the racecourse or at stud, of their direct, or tail-female, descendents. At that time Bruce Lowe identified approximately fifty mares, whose tail-female lines were alive, to which he assigned family numbers, much like a numerical surname. The mare with most Classics winners was given the family number 1, the mare with the second most Classics winners was given the family number 2, and so on. These family numbers are still in use today, and in many parts of the world are considered much more significant than in North America. At the very least they draw attention to the fact that there is more to a horse than simply the sire line. For a more detailed history of Bruce Lowe and his contemporaries, and an explanation of his figure system visit The Bruce Lowe Home Page.

Later, Captain Kaziemierz Bobinski and Lt-Colonel Stefan Count Zamoyski collaborated to produce Family Tables of Racehorses. In order to accomodate more horses Bruce Lowe's  numbering system was expanded as follows:

Families 1-74 trace directly to a mare in the General Stud Book
Families 1-49 are numbered according to Lowe and Goos
Family 50 has been restored to Family 13
Family 51 is comprised of the descendants of the King William IV Arabian Mare (as in Keylock)
Families 52-74 remain unclassified or without a number designation
Families Ar1-Ar2 are Argentine families
Families P1-P2 are Polish families
Families A1-A37 descend from American Stud Book mares who cannot be traced to the GSB but which are accepted as foundation mares
Families C1-C16 are described in the Australian Stud Book as approved Colonial Families
Families C17-C33 descend from Australian and New Zealand mares who cannot be traced to the GSB
Families B1-B26 trace directly to Prior's Half-Bred Studbook

Having issued some 6 or 7 updates, Bobinski took all the updates, added a year or two to them and reissued the Family Tables as Vol II in the 1963. After Bobinski's death, Toru Shirai of the Japanese Bloodstock Agency purchased the copyright and in 1988 he issued Vol III of the Family Tables, bringing the Tables up to 1987. In 2004 the Japanese Bloodhorse Breeders' Association issued Volume IV of Family Tables of Racehorses.

Jersey Act (1913-1949)
From its roots in England the thoroughbred racehorse spread over the earth, sometimes returning to be measured against the best. Although he wasn't the first, none did so with more success than Gladiateur (b c 1862 Monarque), or with more shock to the English turf, as he had and his parents had been bred in France. Gladiateur won the English triple crown, the French St Leger and the Grand Prix De Paris in 1865 and won the Ascot Gold Cup in 1866. The French press called him the "Avenger of Waterloo," but hyperbole aside, he was indeed a portent. Kincsem (ch f 1874 Cambuscan) came from Austria-Hungary in 1878 to win the Goodwood Cup. Iroquois (br c 1878 Leamington) came from America to win the Derby, St Leger, St James's Palace Stakes and Prince Of Wales's Stakes in 1881. Foxhall (b c 1878 King Alfonso) also came from America to win the 1881 Cesarewitch, the Cambridgeshire and the Grand Prix De Paris and to win the Ascot Gold Cup the following year. Merman (ch c 1892 Grand Flaneur) came from Australia to win the Cesarewitch in 1897, the Jockey Club Cup in 1898, the Goodwood Cup in 1899 and the Ascot Gold Cup in 1900.

Around the turn of the 20th century, the keepers of the General Stud Book became increasingly concerned with the importation of foreign horses into England. In Volume 18 (1897) they noted they were content to refer to the stud books of origin, but uncomfortable with the notion that in all cases an unbroken connection to the GSB was not maintained. After referring to the Stewards of the Jockey Club they stated in Volume 19 (1901) that "any animal claiming admission should be able to prove satisfactorily some eight or nine crosses of pure blood, to trace back for at least a century, and to shew such performances of its immediate family on the Turf as to warrant the belief in the purity of its blood. Therefore all the imported horses and mares, which are included in this Volume, have been submitted to this test".

One victim of this ruling was the Australian-bred Newhaven (ch c 1893 Newminster) who did not have the requisite 8 crosses and descended from a mare named Dinah (Family C5) whose pedigree had been lost. Newhaven had been a splendid racehorse in Australia and after his importation in 1897 won the City and Suburban Handicap in England. He retired to the Warren Stud at Newmarket but despite his superior racing ability, after having been virtually labelled a Half-Bred, could attract no patronage so was sent back to Australia a few years later.

In America horse-racing was itself in great distress. Anti-gambling legislation had crippled the bloodstock industry. Racecourses had closed. Many things American came to Britain along with more horses, including American jockeys, lighter racing plates, differing styles of horse management, diet and doping. Not all things were bad, not all things were good, but to the ordinary English breeder it was frightening to behold the flooding of their market with both. They couldn't prevent the influx of trade, but they could control its pedigree.

In Volume 21 (1909) the General Stud Book rescinded the notice of Volume 19 and instead required that "no horse or mare can be admitted unless it can be traced to a strain already accepted in earlier volumes of the Book". In Volume 22 (1913) a suggestion initiated by Lord Villiers, later the Earl Of Jersey, was incorporated, that "no horse or mare can, after this date, be considered as eligible for admission unless it can be traced without flaw on both sire's and dam's side of its pedigree to horses and mares themselves already accepted in the earlier volumes of the book". This became known as the "Jersey Act". Although not aimed exclusively at America, much of the dissatisfaction with the ruling came from there, as the pedigree of Lexington (b c 1850 Boston) was considered unauthenticated.

The speedy Americus (b c 1892) arrived in 1895 and was therefore eligible. He had two crosses of Lexington in his pedigree and he sired the 2° dam of Mumtaz Mahal (gr f 1921 The Tetrarch). Nearco (br c 1935) had as his 3° dam the American-bred Sibola (b f 1896), imported in 1898 and winner of the 1000 Guineas in 1899. Sibola's 3° dam was Maiden (b f 1862 Lexington), but Nearco was eligible because of Sibola's import date.

However, conflicts arose, most of them based on the pedigree of Lexington. Orby (ch c 1904 Orme) won both the Derby and the Irish Derby in 1907. His dam Rhoda B., (br f 1895 Hanover) imported as a yearling in 1896 before the restrictions, was unaffected. However, the French-bred Durbar II, (b c 1911 Rabelais - Armenia) who won the Derby in 1914, was. His 2° dam Urania (ch f 1892 Hanover) of Family A4 had Lexington twice in her pedigree. The inconsistency was highlighted when the Goodwood Stakes winner Diapason (b c 1921) was considered ineligible: Hanover appeared twice in his pedigree, legitmately through Orby and illegitimately through his damsire Sir Martin (ch c 1906) who came in 1908.

In 1913 the French Stud Book addressed the matter with a ruling of its own, but less onerous than the English version in requiring only 7 generations free of unauthenticated blood and tracing to those already in either the French or English stud books. As Armenia was imported in 1908, not surprisingly her son Durbar II was then eligible in France, but still not in England. His daughter Durban (b f 1918) became the dam of the leading sire in France in 1940, 1942 and 1945, Tourbillon (b c 1928 Ksar). Tourbillon's son Djebel (b c 1937) won the 2000 Guineas in 1940 and after the war came the Ascot Gold Cup winners Caracalla II (b c 1942 Tourbillon) and Arbar (b c 1944 Djebel), the 2000 Guineas winner My Babu (b c 1945 Djebel) and the American-bred St Leger winner Black Tarquin (br c 1945), who was ineligible due to Man O'War, the sire of his 2° dam. Man O'War was ineligible due to his great grandsire Spendthrift (ch 1876) whose dam was by Lexington.

By this time it was apparent that control of pedigree was in fact also a control on the quality of horses available to the English bloodstock industry. In Volume 31 (1949) the ruling of Volume 22 (1913), the so-called "Jersey Act," was rescinded and replaced by the ruling of Volume 19 (1901) to apply for Volume 32 (1953). These were the same conditions that allowed a Half-Bred to pursue Stud Book status, as did Lavant (b f 1955 Princely Gift) who appeared in Volume 36 and subsequently many others. In Volume 36 (1969) the keepers attempted to clarify the language and introduced a refined requirement for admission for eligibilty in the General Stud Book. It stated that any horse must be able:

1   To be traced at all points of its pedigree to strains already appearing in pedigrees in earlier volumes of the General Stud Book, these strains to be designated "thoroughbred", or,
2   To provide satisfactorily eight "thoroughbred" crosses consecutively including the cross of which it is the progeny and to show such performances on the Turf in all sections of its pedigree as to warrant its assimilation with "thoroughbreds".

This was later adopted by the International Stud Book Committee. This has the further advantage that it ensures that a pedigree accepted by one stud book will be recognised by all stud books.