Lexington was by the Hall of Fame inductee, Boston (by Timoleon by Sir Archy), from Alice Carneal by Sarpedon.

Lexington stood 15.3 hands (63 inches, 160 cm) and was described as having good conformation though he had a distinctive "moose head" profile.

A syndicate made up of Richard Ten Broeck, General Abe Buford, Captain Willa Viley, and Junius R. Ward, bought Lexington for $2,500 between heats (or during the running of his race), so tried claiming the purse money when he won.

[5] Lexington stood for a time at the Nantura Stock Farm of Uncle John Harper in Midway, Kentucky, along with the famous racer and sire, Glencoe.

[4] He stood for a limited public fee of $500, the highest in the country and comparable to the leading English stallions, in 1865 and 1866 before being restricted to private stud duties only.

[4] Called "The Blind Hero of Woodburn", Lexington became the leading sire in North America sixteen times, from 1861 through 1874, and then again in 1876 and 1878.

Among his noted progeny are: [10] [11] [12] [13] [14][9] [15] Lexington's three Preakness Stakes winners equaled the record of another great sire, Broomstick.

[16] During the American Civil War, horses were forcibly conscripted from the Kentucky farms to serve as mounts in the bloody fray.

[18] Lexington's dominance in the pedigrees of American-bred Thoroughbreds, and the fact that the British Thoroughbred breeders considered him not a purebred, was a large factor in the so-called Jersey Act of 1913, in which the British Jockey Club limited the registration of horses not traced completely to horses in the General Stud Book.

[22][23] However, his influence on the pedigrees of the modern Thoroughbred can still be felt through his daughters, who produced winners Spendthrift, Himyar, Hanover, and Bramble.

[27][28] Likewise, the Spendthrift line has survived into the 21st century through Tiznow, who won the Breeders Cup Classic in consecutive years (2000, 2001); he in turn produced 2008 Belmont Stakes winner Da' Tara, and 2008 Santa Anita Derby and Travers Stakes winner Colonel John.

[2][29] Some of the horses in Lexington's pedigree cannot be traced back to England's General Stud Book, a fact that can probably be attributed to the disruptions and sometimes hazardous record keeping in the period between the American Revolution and Civil War.

[1] The pedigree shown on The Jockey Club's Equineline database is thus incomplete, not showing the dams of Timoleon, Florizel and the Alderman Mare.

However, the mitochondrial DNA of descendants of Lady Grey is inconsistent with that of other members of family 12-b, indicating a likely mismatch.