With capital backing from the Learmonth family, a Scottish entrepreneur in Australia, Mr. David Harkness McKellar, an emigrant from Australia and New Zealand in the late 1880's, purchased over 250,000 acres in Coahuila and founded La Mariposa Ranch in 1890.

The ranch sat in an open valley formed by a fork of the Santa Rosa Mountains which marked the western and northern boundaries and protected it from the cold north winds in winter. These mountains yielded from its canyons an almost inexhaustible supply of cedar and oak timber for fencing and building purposes. The eastern boundary faced the open plains country.

The southern boundary was originally marked by the Sabinas River, a beautiful clear mountain river, ever-flowing and fringed by large cypress trees. Well stocked with fish, it was not only a place of recreation, but also provided a pleasant change of diet. In later years, after the expropriation of 10,000 acres of land by the government, the boundary was moved further north.

Pastures were traversed by creek beds, called arroyos, which provided additional watering areas for the cattle. There were ten natural springs, nine being ordinary water and the other a mineral water spring. Soil on the southern half was a good red chocolate and the northern half a combination of sandy loam and a black, friable earth.

Grasses and forage plants thrived exceptionally well in this region, growing much taller than in Colorado or southern Texas. The stony soil helped preserve the moisture at the root of the plants. The nutritious Gramma grass, well known among ranchers, was abundant in the area. Bermuda, mesquite, sotol, palmetto and guajillo grew wild in the area and were much sought after by the stock. The nopal, or prickly pear cactus, grew abundantly in the canyons.

At an altitude of 1800 to 2500 feet, the ranch enjoyed a semi-tropical climate with 23 inches average annual rainfall. Thus it was a pleasant residence both winter and summer.