The three founding sires of the Thoroughbred were the Godolphin Arabian, the Darley Arabian and the Byerly Turk.

The Byerly Turk was probably an Arab. A Captain Byerly captured this horse from the Turks at the siege of Buda and rode him in the Battle of the Boyne in 1690. Although he was not bred to many mares, he founded a line of Thoroughbreds, the most famous of which was Herod, who became a famous sire.

The Darley Arabian was foaled in Syria in 1700 and bought by Thomas Darley in 1704. The horse was shipped to England and bred to many mares. The Darley Arabian was the great-great-grandsire of Eclipse - one of the most famous racehorses of all time.

The Godolphin Arabian was born in the country of Yemen. He was then shipped to Syria and then to Tunis, where he was given to the King of France as a gift. Legend has it that he became a
neglected work horse on the streets of Paris until he was admired by an English gentleman named Edward Coke, who bought him and shipped the horse back to his home in England. The second Earl of Godolphin eventually aquired the horse and bred him to numerous mares. He sired Lath, one of the greatest racehorses in England. In 1850, it was remarked that "the blood of the Godolphin Arabian is in every stable in England."