The roots of the Idaho Press go back to December 1883 in Caldwell — with the first paper coming off the press just months after Caldwell was established as a city. Nampa city was established in 1885. The newspapers and their competitors underwent several name changes in both towns. Ownership changed often, too. The early versions of the papers were often informational instruments for political parties and movements. And for you trivia buffs, Idaho Gov. Frank Steunenberg, who was murdered at his home, was one of the first editors and publishers of the Caldwell Tribune, a forerunner of today's Idaho Press. Jumping forward several decades, The Scripps League bought the Idaho Free Press in 1954 and the Caldwell News Tribune in 1956. Subsequent transactions eventually resulted in the ownership of the two Canyon County newspapers by Pioneer Newspapers in 1975.

In February 1980, the two papers were merged, becoming the Idaho Press-Tribune, and the first Sunday morning newspaper was delivered. In mid-1990 the Emmett Messenger Index, a weekly Gem County newspaper, became part of the Idaho Press-Tribune family. The 2010s were a decade of rapid growth for the Idaho Press-Tribune family of publications. In 2013, the Idaho Press-Tribune launched the Meridian Press and, in 2016, it purchased the Kuna Melba News. In 2017, Adams Publishing Group purchased the Pioneer News Group, making Adams the largest owner of newspapers in Idaho with daily newspapers in Nampa/Boise, Blackfoot, Idaho Falls, and Pocatello and weekly newspapers across southern Idaho.