The Flemish Giant originated in Flanders. It was bred as early as the 16th century near the city of Ghent, Belgium. It is believed to have descended from a number of meat and fur breeds, possibly including the Steenkonijn (Stone Rabbit—referring to the old Belgian weight size of one stone or about 3. 8 kilograms (8. 4 lb)) and the European "Patagonian" breed (now extinct). This "Patagonian" rabbit, a large breed that was once bred in Belgium and France, was not the same as the Patagonian rabbit of Argentina (Sylvilagus brasiliensis), a wild species of a different genus weighing less than 0. 9 kilograms (2. 0 lb), nor the Patagonian mara (Dolichotis patagonum), sometimes called the Patagonian hare, a species in the cavy family of rodents that cannot interbreed with rabbits.
Thomas Coatoam, in his Origins of the Flemish Giants, tells us, "The earliest authentic record of the Flemish Giant Rabbit occurred about the year 1860. "