On 29 April 1820, George Frederic Augustus signed a document granting MacGregor and his heirs a substantial swathe of Mosquito territory—8,000,000 acres (12,500 square miles; 32,375 square kilometres), an area larger than Wales—in exchange for rum and jewellery. The land was pleasing to the eye but unfit for cultivation and could sustain little in the way of livestock. Its area was roughly a triangle with corners at Cape Gracias a Dios, Cape Camarón and the Black River's headwaters. MacGregor dubbed this area "Poyais" after the natives of the highlands around the Black River's source, the Paya or "Poyer" people (today called the Pech), and in mid-1821 appeared back in London calling himself the Cazique of Poyais—"Cazique", a Spanish-American word for a native chief, being equivalent in MacGregor's usage to "Prince". He claimed to have been created such by the Mosquito king, but in fact both the title and Poyais were of his own invention.