In my message dated January 26, 2003, the Regan to whom referred was probably Timothy A. Regan. His parents were Morgan and Mary (Burke) Regan of Wisconsin (emigrated from Ireland, stopped first in Maine, then resided in New York for a few years, and then moved to Wisconsin). At least three of his brothers, William V., Stephen F. and Philip A. Regan also made their appearances in Idaho, but Tim is the one who was more widely known in Ada and Owyhee counties, Idaho. Timothy arrived in Jordan Valley, Oregon (near the Idaho border) in November, 1864, and then walked to Silver City, Idaho, a new mining town in the Owyhee Mountains. He moved to Boise in 1889, having acquired a good deal of assets during his early years in Owyhee County through mining investments. If you have access to the book, "Syringa Blossoms," by J. D. Flenner, there is an interesting biography (and photo) of him on pp. 42-46. I should mention that in 1912, two sons of Timothy and Rose C. (Blackinger) Regan, were both in business in Boise.
Elizabeth L. Cuff