Eclipse was bred in 1764 by the Duke of Cumberland. He was foaled at either Cranbourne or Cumberland Lodge, in Windsor Park, although local pride has given him as many other birthplaces as Homer. He was exceptionally big for his time - 15.2 or 15.3 - but his height is a matter of perennial debate. George Stubbs, (1724-1806) who painted him as a six-year-old, does not show the unusual conformation on which many contemporaries remarked: his quarters were perceptibly higher than his withers. Descended from the Darley Abrabian breed of horse, his lineage is with the modern Thoroughbred. Thoroughbred racehorses are descended from Arab stallions. The History of Horse Racing by Roger Longrigg, pages 82 and 83.