In the late 1870's men pushed into Montana hoping to mine the precious ore from the mountains. But the mining operations needed support; they needed a railroad to bring in equipment and food for miners. As a consequence of the railroad and mining activities, many men were exposed to the fertile Snake River Valley. Later some of these men returned to the valley and claimed land, a privilege granted by the Homestead Act of 1862.

The Rexburg area in its infancy revealed a much different picture than we see today. It was very sparsely settled with only a few fur trappers and an occasional cattle operation. The first known white men into the area were fur trappers. One man who continued trapping in the Rexburg area was the colorful Richard Leigh otherwise known as "Beaver Dick".

Interest in the Rexburg area seemed to quicken in 1879, however, when a man named John Poole spent some time hunting around Menan while employed by the Utah Northern Railroad. Poole returned to Utah and told of good farmland in the area. Mormon Church people heard Poole's praises and in 1882 the Mormon President, John Taylor, instructed W. B. Preston and Thomas E. Ricks to make a trip to the Upper Snake River Valley to scout out a site for a settlement.

Additionally, a group of young Mormon men from Cache Valley, Utah, was organized to form a settlement in the area. Among these men was Thomas E. Ricks, founder of both Rexburg, and Ricks College (now BYU-Idaho). In February 1883, they cut logs for building a community in the spring. In March the men met at the present town site of Rexburg and constructed the first log house. The settlers first decided to call their town Ricksburg after their settlement leader, Thomas E. Ricks. However, since the German ancestral name of Ricks is Rex the town's name was changed to Rexburg.

While the settlers worked on their log houses most of them lived out of dugouts or tents pitched on the banks of the Teton River. Many settlers called it "Mosquito Flats" because of the hordes of mosquitoes from the nearby sloughs.

Thomas E. Ricks began the first mercantile located just across the street from the courthouse and in 1884 Thomas E. Ricks and Company Flour Mill began operations just four months after he publicly stated they needed one. The original mill burned down and another was built to replace it.

Henry Flamm was also a prominent figure in Rexburg. He was the founder of a commercial enterprise known in those difficult early days for its lenient credit policy. Flamm was Rexburg's chairman for two terms 1893 and 1894 and became the first Mayor when city status was achieved in 1903.

The residents of the village of Rexburg under the direction of Ricks and his associates seemed to accomplish more in two years building canals, roads, schools and general improvements than was usually accomplished in five years anywhere else.