Plymouth is a small rural community that lies approximately thirty miles north of Brigham City. It was first settled in 1869 by Harmon Pierson, Isaac Zundell, John Taylor, and William and Joseph Merrell. They lived in tents the first summer, and in the fall they laid out a one-block townsite which was divided into lots. Like Israel of old, they cast lots for their part and each set up his tent on the site he drew. For many years Plymouth was known as Square Town. In the fall, three log cabins were erected.
The area provided good grazing and farming. A reservoir was built, and the water was used to power a saw mill. Much of the lumber was used in the home construction in Bear River City and in the construction of Plymouth’s first school in 1871. The school district was known as Zarahelmla.
In 1886-1887 George Mason established a dairy at Mound Springs located about four miles north of Plymouth on land formerly owned by James Cole, a member of the Mormon Battalion. Mound Springs, first settled in 1874, was a stopping place for emigrants. Butter and cheese were made, and the dairy employed seven or eight people.
For many years Plymouth was a part of the Portage Ward, with Harmon Pierson serving as presiding elder without counselors. In 1884 the Plymouth Ward was organized with Myron J. Richards as bishop. The ward included what is now Riverside, Fielding, and Plymouth. Thomas Archibald was made bishop of Plymouth Ward. When the John W. Hess family and others came from Davis County, they settled north of the present site of Fielding, and on June 18, 1891, the East Plymouth Ward was taken from the Plymouth Ward, with Myron J. Richard as bishop in the new ward.
The first post office was in the home of Harmon D. Pierson. Garrett Wolverton carried the mail from Corrine north to Plymouth. Later, Ben Williams of Malad carried the mail from Collinston. A post office was established in the early 1880’s, with Don Lamb as the first postmaster.
It is said that the name of Plymouth came from an observation made by one of the early inhabitants. Out for a walk with others, they came upon a large rock, and she observed that it resembled Old Plymouth Rock. All agreed that this would be a good name for the town, and Plymouth replaced the name of Square Town.