No one knows who first settled Pleasant Mound in 1856, as several settlers came to the area around the same time that year. Pleasant Mound went through a few name changes before settling on its current name; when the township was first named on April 6, 1858, to “Otsego,” but they changed its name to “Willow Creek” on October 14, 1858. Its current name was chosen by F. O. Marks, a settler who established a post office at his home in 1863. He called the post office “Pleasant Mound” after the chain of mound-shaped hills that towered up to seventy-five feet above the Minnesota prairie. Marks’ post office was not the only post office in the area for long; the town created another post office that year with T. H. Day as its postmaster. These post offices ran weekly mail routes between Garden City and Fairmont.
In 1865, the township was officially created and named “Pleasant Mound,” at Marks’ suggestion, and the first meeting was held September 26, 1866. While most of the settlers were Americans, they did not linger in the area long. In June of 1866, a large German Lutheran Colony came and settled in the township. At first, religious services were held in people’s houses, but in 1869, a combined church and parsonage was constructed. Reverend J. C. Mueller was its first pastor. In April of 1872, the building burned down, but later that summer it was rebuilt as two separate buildings. Two parochial school buildings were added in 1881. The first teacher was Frederick Zink. Over the years, a new church building had to be constructed due to the expanding population, as well as a new school house in 1908, and houses for school teachers were built next to the schools.
The Pleasant Mound post office and the Willow Creek post office were both discontinued in 1902. There was also brickyard started in 1860 that did very well, in addition to the John S. Parks’ apple orchid with over two hundred varieties of apples and a creamery that was built in 1896. Though Pleasant Mound faced disasters like wind storms and even an alleged murder in 1889, it was known in its early days as one of the most prosperous townships in Blue Earth County.