In the late 1600s Jesuit missionary and explorer Father Eusebio Kino established a herd of Spanish horses along with cattle and other livestock at Mission Dolores, Mexico, to supply the expanding settlements of the Pimeria Alta region. In the 1970s, according to family history, Dr. Wilbur, an early homesteader near the town of Arivaca, Arizona, purchased a group of these mission horses. These became the foundation stock of the Wilbur-Cruce rancher strain of the Spanish Barb breed. Dr. Wilbur's granddaughter, Eva Antonia Wilbur-Cruce, preserved this isolated herd through much adversity until she sold her family ranch in 1989 to The Nature Conservancy to be included in the Buenos Aires National Wildlife Refuge. Fortunately the American Livestock Breeds Conservancy became involved. Blood typing and visual inspection supported the oral history and resulted in the rescue of the herd. Today Eva's "rock horses," as she fondly called them - noting their ability to negotiate very difficult, rocky, mountainous country with skill and ease - are preserved in several Western states. In 2005 the Wilbur-Cruce horses were formally accepted as the sixth foundation strain of the Spanish Barb. Today the Wilbur-Cruce Spanish Barbs are highly prized for their extraordinary hardiness, sure footedness and strong bond with 'their' people.