Gilmore City is located on the county line midway between Humboldt and Pocahontas in Section 6 of Weaver Township. The town was incorporated in 1876. In 1878, a twice weekly mail route was established between Humboldt and Pocahontas. The post office was located in the farm home of Sewell Van Alstine, but it was his wife, Ellen, that had been appointed post mistress.

Mr. Van Alstine's daughter, Althea, had named the town Blooming Prairie. When the early settlers came to the county, the prairie was covered with luxurious growth of grass and flowers. In the very early spring it was blue with violets, and later, wild strawberries were abundant.

In 1882, when the Minneapolis & St. Louis Railroad line was pushed through to the town.  The name of town was then changed to Gilmore City, after C. N. Gilmore. Mr. Gilmore was the Superintendent of the line. The first railroad agent was C. S. Cooley from 1882 to 1891.

The post office was moved to town, and L. E. Childs was the first postmaster, serving from 1882 to 1886. Mr. Childs, also was the first to build a store building in 1882.

James Bothwell built one of the first houses in Gilmore City. The first bank, Gilmore Exchange Bank, was established in 1886 by Levi Garlock. Leslie H. and Howard S. Van Alstine purchased the bank in 1887. A second bank, Security, was established a little later by Rollin Van Alstine and Lyman Beers.

Percy Beers was the town's first lawyer. C. W. Edgington owned the local elevator, and grain dealers were Mullen and Hunter. L. L. Van Alstine had the harness sore and livery stable was owned and run by Will Cavanaugh. The photographer was Dan Rice. The first barber was Charlie Kennedy who later owned the Kennedy candy store. The lumber and coal yards were run by Black and Frank Neel. The early carpenters were Albert Freeman, William Barker and C. L. Belt.

L. E. England was the first druggist. Dr. Coffin was the first physician, followed by Dr. McManus and Dr. A. L. Belt. William Saxby was the Veterinarian.

C. L. Hatfield was the general merchant. By 1892, the Gilmore City Globe was started by W.R. Prewett, followed in 1893 by H. C. Marmon who edited the paper for many years.

The limestone quarries north of Gilmore City supplied rock for many of the first business buildings and also the first school on the Humboldt county side of Gilmore City. In 1911 a cement plant was established just one mile north of town and flourished until the depression. In 1931 it was purchased and closed by McNiders of Mason City.