Founded by Jud L. Sedwick, the company was headquartered in Kittanning, Armstrong County, in Pennsylvania.

Together with his brother Ned, Sedwick ran two crews consisting of six men each, whose job consisted of hanging telephone lines, setting telephone poles, and clearing right of way throughout western Pennsylvania, and managed to grow the company to 12 crews by the end of its first year of operations.

The company's headquarters are in Butler County, western Pennsylvania, with local offices scattered throughout the region.

Originated in 1950 by purchasing Ritchie Telephone Company in Harrisville, West Virginia, Armstrong owns and operates independent telephone companies in West Virginia, Maryland, Pennsylvania, and New York.

(2014 & 2015) Internet Service Providers were ranked at the bottom of Consumer Reports lists for those years.

In that same year, Armstrong donated over $1 million in the form of "in-kind cable access" to American Crossroads, a Republican Super PAC.