Dahlia was a chestnut mare with a narrow white blaze bred and owned by the Texas oilman Nelson Bunker Hunt.
[2] Dahlia was the first foal of her dam Charming Alibi, a durable racemare who won sixteen of her seventy-one races and earned over $110,000 in prize money.
[7] Dahlia began her second season in April in the Prix de la Grotte, a trial for the Poule d'Essai des Pouliches over 1600 metres at Longchamp, and won easily from Gay Style.
Ridden as usual by Bill Pyers, and starting at 5.4/1, Dahlia overtook Virunga early in the straight and won by one and a half lengths, with Kashara taking third ahead of Princess Arjumand.
The British filly Mysterious started odds on favourite after wins in the 1000 Guineas and The Oaks, whilst Dahlia was second choice on 8/1 alongside the Pretty Polly Stakes winner Hurry Harriet.
Dahlia moved up to challenge Mysterious a quarter of a mile from the finish, overtook the favourite a furlong out and drew away to win easily by three lengths.
A week after her win in Ireland, Dahlia took on older horses for the first time in Britain's most prestigious weight-for-age race, the King George VI and Queen Elizabeth Stakes at Ascot Racecourse.
Dahlia's third clash with Allez France in the Prix Vermeille saw her start a slight favourite ahead of her rival in a field which also included Virunga, Gay Style and Hurry Harriet.
The other European challengers were Scottish Rifle, Hurry Harriet, Card King (fourth in the Arc) and Acacio d'Aguilar (Preis von Europa), whilst the "home team" comprised Tentam (the 7/10 favourite), Big Spruce and London Company.
She was given what was described by Timeform as a "preposterous task" by her jockey as she trailed the field by many lengths in the early stages before making progress in the straight and finishing third behind Buoy and Tennyson.
Ridden by Lester Piggott, she started 15/8 favourite against nine opponents including Highclere, Snow Knight, Dankaro, Buoy, Card King, Orsa Maggiore (Oaks d'Italia) and Hippodamia (entered as a pacemaker for Dahlia).
Piggott restrained the filly towards the rear as Hippodamia set a strong pace from Snow Knight and Buoy, before moving up to fourth on the final turn.
[11] Despite reports that she would spend the rest of the season in North America, Dahlia was back in England in August and started 8/15 favourite for the third edition of the Benson and Hedges Gold Cup over ten and a half furlongs at York Racecourse.
[12] Highclere and Snow Knight were again in the field along with Imperial Prince (runner-up in the Epsom and Irish Derbies), whilst Hippodamia was again there to set the pace.
The filly bypassed the Arc and ended her season with three races in North America, starting with the Man O' War Stakes at Belmont Park on 11 October.
With Piggott suffering from an ear infection which meant he was unable to fly to the United States, Dahlia was ridden by Ron Turcotte and came from well off the pace on the final turn to win by two lengths from Crafty Khale, with London Company taking third ahead of Golden Don.
In her attempt to win a third King George VI and Queen Elizabeth Stakes, she produced her best effort up to that point in the season despite becoming agitated in the preliminaries and showing a reluctance to enter the starting stalls.
Ridden by Piggott and starting at 6/1, she stayed on in the straight and finished third to Grundy and Bustino, ahead of On My Way, Card King, Ashmore and Star Appeal.
[15] Dahlia's attempt to repeat her 1974 win in the Benson and Hedges Gold Cup saw her start at odds of 7/2 behind the odds-on Grundy with the other runners being Card King, Star Appeal and the outsiders Jimsun and Meautry.
Dahlia led from the start, and with Piggott winding up the pace from early in the straight she won easily from Card King and Star Appeal, with Grundy running poorly in fourth.
In the Grand Prix de Deauville on 31 August she finished third behind Duke of Marmalade and L'Ensorceleur but was promoted to second when the winner was disqualified.
In late autumn she was again sent to North America and ran twice, starting with a fourth place behind Snow Knight in the Canadian International, in which she was given a great deal of ground to make up in the closing stages by her jockey Sandy Hawley.
[17] In all, Dahlia had 48 starts, for 15 wins and 3 seconds and 7 thirds, defeating Classic-winning colts, in England, Ireland, France, Canada and the United States for $1,489,105 in prize money.
[19] At the end of the 1976 racing season, Dahlia was retired and went on to a top record as a broodmare,[citation needed] something uncommon among great racemares.