Ornithological investigations in Arizona were begun in the 1850s by medical doctors attached to military posts. Studies in the Tucson region increased after establishment of several additional post-Civil War forts during the mid-1860s. From then into the early 1900s ornithologists used Tucson as a base from which to investigate the surrounding valleys and mountains. Allan R. Phillips was Arizona’s first resident professional ornithologist and contributed more than any other single person to the establishment of ornithology as a viable science in Arizona. Earlier ornithologists had been either nonresidents or, like Herbert Brown, were amateurs. Phillips worked full-time as an ornithologist for 60 years. As “Dean of Southwestern Ornithologist” his position gave him unprecedented independence among contemporary workers. His contributions to avian systematics and distribution exceed that of any recent ornithologist in the North American Southwest (SW US and NW Mexico) and the remainder of Mexico.