Janus (1746–1780),^[1] also known as Little Janus, Young Janus, and Janus II, was an English Thoroughbred stallion imported to Colonial America, which would later become the United States.^[2] Noted for his quickness and compact conformation, he has subsequently been acknowledged as a foundation sire of the American Quarter Horse.^[3]

Bred by Francis Godolphin, 2nd Earl of Godolphin, Janus was foaled in England in 1746. He was a grandson of the Godolphin Arabian, and like his grandsire, was chestnut in color.^[4] Subsequently, owned by Anthony Langley Swymmer, a founding member of the Jockey Club and an English MP.^[5] He raced under various names including Little Janus and Stiff Dick. His English racing career took place between 1750 and 1752. Janus won twice at 4 miles and was retired due to injury. Janus was sold to George Grisewood, a horse breeder and turf enthusiast.^[6]

After becoming lame, Janus was imported to Virginia Colony by Mordecai Booth in 1752,^[7] and resold to Mildred Willis.^[8]

Janus was able to fully recover and went on to race again.^[9] He won races in Virginia and North Carolina.^[10] Janus was compact, standing just over 14 hands (56 inches, 142 cm), yet large boned with powerful hindquarters.^[11][12][13]

In late 1771 or early 1772 he was sold to Jeptha Atherton and was moved to North Carolina.^[14][15] In 1773 he was at stud at what would later become Northampton Courthouse, in Jackson, North Carolina.^[16][17]

Janus died in 1780, aged 34. His offspring included Celer, foaled in 1774, and Spadille.^[18]

Manly Wade Wellman wrote a fictionalized account of the life of Janus.^[19]