Queen Mary was bred in Yorkshire by Mr Dennis of Holderness, near Beverley, who perspicaciously sent her dam to Gladiator (ch c 1833 Partisan) in 1842, as the stallion advertisements for 1843 noted that "Lord Chesterfield and Colonel Anson and most of Scott's masters have sent nearly all their favourite mares to Gladiator and Jereed, and the stock of both have turned out amazingly well."

Queen Mary was purchased as a yearling by Mr William R Ramsay of Barnton, near Edinburgh, who sent her to William I’Anson at Gullane, also near Edinburgh, for training. In her only start, in May of 1845 at Chester, she fell, sustaining injuries that terminated her racing career. As a result she was subsequently acquired for £30 by her trainer who greatly admired Gladiator.

I'Anson sent her to Lanercost (br c 1835 Liverpool) to whom she duly produced Haricot in 1847. Haricot, scarcely taller than a pony and blessed with unfortunate conformation, disappointed to the extent that I'Anson did not bother to put her in training. Queen Mary produced her next living foal, Braxey, to Moss Trooper (br c 1839 Liverpool) in 1849 and Braxey failed to offer much improvement. Thus when I'Anson moved his training operation to Langton Wold, near Malton, he sold Queen Mary to a Forfarshire farmer for £40.

Having little aspiration for Haricot I' Anson used her as a hack until an exercise gallop in which she so impressed him that he put her into serious training. She won ten races in her first season and during her career she ran forty times winning seventeen races including the Stirling Gold Cup, the Lincolnshire Handicap and the Manchester Cup. As a five year old she was beaten only a head by Voltigeur (br c 1847 Voltaire) in the Flying Dutchman Handicap at York. Given Haricot’s success I’Anson set about reacquiring Queen Mary. Fortuitously he found her on the same Forfarshire farm where he had originally sold her. No doubt the farmer must have realised that I’Anson had good reason for wanting her back and was not going to be so sporting as to let her go for the price he paid. She was, the farmer reasoned, in foal; so after some negotiation the price agreed upon was £100. To his consternation I'Anson discovered that the farmer had had her covered by a Clydesdale stallion, to which she produced a half-bred foal in 1851.

Queen Mary had nineteen foals, of which two died young and one was half-bred. Queen Mary herself is the taproot mare of Family 10-a. Four of her daughters have branches of Family 10-a assigned to them: Bonny Bell, taproot mare of Family 10-b, Bonnie Doon, taproot mare of Family 10-c, Braxey, taproot mare of Family 10-d, and Blooming Heather, taproot mare of Family 10-e. Both Haricot and Blink Bonny were very successful in the stud as well. Queen Mary died in 1872.