The settlement and development of Mt. Pleasant followed the typical pattern for Mormon towns of the period. A square-shaped townsite was surveyed (eventually containing about 100 city blocks), lots were drawn, and the land was distributed among the population. Under the direction of James Ivie, a fort of adobe walls and log cabins was built. Pleasant Creek ran through the fort and farming was done outside of its walls. By the time the final peace treaty with the Indians was signed in Bishop Seely's house on Main Street in 1872, bringing to an end the Black Hawk War, many settlers had already erected homesteads outside of the fort. Although the townsite is large in scale, the density is relatively low due to the original layout allowing for only four lots per block.

Mormon influence was felt in all religious, political, economic, educational, and social aspects of life in early Mt. Pleasant. Self-sufficiency was a virtue and home-grown and home-manufactured food, clothing, and furnishings were far more available than rarely found imported items. Some of the first industries included tanning, shoemaking, blacksmithing, basketmaking, and freighting. Eventual modernization brought such improvements as the Deseret Telegraph in 1869, the Pyramid newspaper in 1890--still the county's largest--and a telephone system in 1891.