Her descendants include Kentucky Derby winner Go For Gin and champions But Why Not, Princess Rooney, Pleasant Tap and Travelling Victor.
Black Helen was bred by Colonel Edward R. Bradley and was foaled at his Idle Hour Stock Farm in Lexington, Kentucky.
In 1930, Bradley purchased a well-bred mare named La Troienne, in foal at the time to Gainsborough, for 1,250 guineas at the Newmarket sales and imported her to America.
After the Gainsborough foal died, La Troienne was bred to Bradley's foundation stallion Black Toney, a moderate racehorse known for his stamina and toughness.
[8] On July 3, she won by six lengths and set a track record at Arlington Park by running five furlongs in 0:582⁄5, leading the New York Times to call her the best juvenile filly of the season.
[9] A throat ailment kept her from racing during the summer, but she returned on October 16 at Laurel Park, where she ran her winning streak to five when she won the Anne Arundel Purse as the heavy favorite.
[7] On October 30, Black Helen won her seventh straight race in the Pikesville Purse at Pimlico at a distance of one mile and seventy yards.
[14] For her next start, Bradley nominated her to run in the Preakness Stakes where she was expected to be one of the main rivals to Kentucky Derby winner Omaha.
When Vicaress tired after a mile, Bloodroot made her move and opened a length-and-a-half lead on Good Gamble, with Black Helen a length further back in third.
In deep stretch, Black Helen cut over to the rail and closed ground to move into second, then won the race by a nose in the final strides after Bloodroot's jockey eased up on his filly.
)[18] On June 15, Bloodroot turned the tables by winning the Prospect Purse at Washington Park, with Black Helen finishing third in her first loss of the season.
[26] Black Helen produced no stakes winners in her long career as a broodmare, five years of which were spent at Claiborne Farm after Bradley's death.