David M. Mills, who for many years played a prominent part in the development of this part of the state and of the neighboring state of South Dakota, was a native of New Hampshire, but when a youth moved with his parents to Michigan, the family settling on a farm in the Gull Prairie neighborhood, where his parents both spent the remainder of their lives. When about sixteen years of age David M. Mills joined a party en route to the gold fields of California and with that party drove across the mountains and the plains to the new El Dorado. After mining there for some time he bought a threshing-machine outfit, the first of its kind ever seen in California, and for some time operated the same on the Santa Rosa ranch, an immense ranch in south central California, people traveling for hundreds of miles throughout that section to witness the operations of the machine. David M. Mills "made good" financially, in California and remained there for five or six years, at the end of which time he took a sight-seeing trip through South America, the same consuming a year or more. Returning thence to California, he presently came back East, going to Champaign, Illinois, on a visit to a brother, and about the year 1856 came to Iowa, stopping at Sioux City, Whence he shortly after ward went to Sioux Falls, South Dakota, in the employ of the Great Western Land Company, and while thus employed "held down" a pre-emption claim to a quarter of a section of land for the company on the site of the present city of Sioux Falls. After a sometime residence there he came over into this part of Iowa and pre-empted a quarter section of land in Sioux township, this county, paying one dollar and twenty-five cents an acre for the same. He put up a small two-room house on the tract, broke twenty-five or thirty acres of the land and was living there when the Indian scare in 1862 drove the few settlers away from this region. Mr. Mills took his family to Sioux City during the time of the Indian trouble and the family remained there until the spring of 1865, he meanwhile making trips back and forth to his farm and cultivating the same, and at the time just mentioned he moved with his family over to Elk Point, where he established his home and where he remained until the fall of 1872, meanwhile retaining and cultivating his land in this county. During his residence at Elk Point, Mr. Mills served for two years as United States revenue assessor for the territories of the Dakotas, Wyoming and Montana and also served for two terms as a member of the Dakota territorial Legislature. In the fall of 1872 he moved his family back to this county and again settled on his farm in Sioux township, which he proceeded to improve in excellent shape, erecting fine new buildings on the same, planting a splendid grove and other-wise bringing the place up to a high standard of cultivation. As his affairs prospered Mr. Mills bought further land and became largely interested in the raising of cattle and other live stock and soon became recognized as one of the most substantial farmers and stockmen in this part of the state, at the time of his death, being the owner of seventeen hundred and fifty acres, four hundred acres of which lay across the river in the neighboring state of South Dakota. Mr. Mills also took an active part in public affairs, served a term as sheriff of Plymouth county in an early day and helped to lay out the present road between Sioux Falls and Sioux City. He died at his home in Sioux township on April 26, 1893, being then in the sixty-ninth year of his age.

David M. Mills was twice married. It was after his return from California that he was united in marriage to Sarah A. Robertson, who was born on a farm in Elkhart county, Indiana, daughter of Jerome Robertson and wife, who later came to Iowa and made their home for awhile on a farm near Des Moines, whence they returned to Indiana, where Jerome Robertson spent the rest of his life. His widow died at the home of a son in Missouri. Jerome Robertson and wife were the parents of five children, of whom Mrs. Mills was the third in order of birth, the others being Jacob, Jane, Jerome and Henry. Jacob and Jerome Robertson served as Union soldiers during the Civil War and the former was so severely wounded during that service that he never afterward regained his normal physical condition. To David M. and Sarah A. (Robertson) Mills seven children were born, namely: Milo S., the immediate subject of this biographical sketch; Nellie, who died in her girlhood; Lottie, who also died in youth; Agnes, who died on September 1, 1885, at the age of sixteen years; David, who was suffocated while engaged in digging a well on September 16, 1891, he then being twenty years of age; Frank P., a banker at Westfield, this county, a biographical sketch of whom is presented elsewhere in this volume, and George, who was drowned in the Big Sioux river on March 16, 1890, he then being thirteen years of age. The mother of these children died in March, 1881, at the age of forty-five years, and in 1883 Mr. Mills married Jennie T. Gage, who survived him seventeen years, her death occurring on July 10, 1910.

~Source: History of Plymouth County, Iowa. Indianapolis, Ind.: B. F. Bowen, 1917