From the Wikipedia page [1]

The Western History Association (WHA), a 501(c)(3) non-profit organization, was founded in 1961 at Santa Fe, New Mexico by Ray Allen Billington et al., with the following mission: "The Western History Association strives to be a congenial home for the study and teaching of all aspects of North American Wests, frontiers, homelands, and borderlands. Our mission is to cultivate the broadest appreciation of this diverse history." Included in the field of study are the American West and western Canada. The Western History Association was headquartered from 2012-2017 at the University of Alaska, Fairbanks.[2] As of 2018 the WHA is hosted on the campus of the University of Nebraska at Omaha with the support of the Department of History, College of Arts and Sciences.

The website is [2].