The town of Rosemount is situated in the northern central portion of Dakota county, bounded on the north by the towns of Eagan and Inver Grove, on the east by Nininger, on the south by the towns of Vermillion and Empire, and on the west by the town of Lebanon. It is a fraction of over four miles from north to south, and nine miles east and west, embracing 22,201 acres of land. The board of county commissioners, in accordance with an act passed by the first state legislature, designated congressional township 115 north, or range 19 west, of the fifth principal meridian, by the name of Rosemount, at a meeting held April 6th, 1858. In February, 1871, by an act of legislature, the west half of township 115 north, of range 18 west, was annexed to Rosemount. This tract was at that time a part of Inver Grove, it having been detached from the town of Nininger by the county board, September 18th, 1858, and attached to Inver Grove. The north-western portion of Rosemount was covered with a growth of small timber, when first settled. The clearing made for farming purposes has changed the appearance, so that at the present time, only occasional groves are seen.
In the north-eastern part of the town the timber was of a heavier growth, consisting of elm, ash, soft maple and other varieties. The remainder of the town is prairie, slightly rolling in the north and more level in the south.
The soil is principaly a black loam, with clay sub-soil, and on the knolls is rather sandy. In the north-eastern part, along the river, the soil is a gravelly loam.
The only lake of importance, is Keegan's lake, in sections 21 and 20, township 115, range 19. It covers about eighty acres, and has sandy shores and bottom; the depth is about twenty feet in the deepest place. Spring lake, on section 16, township 115, range 18, covers about one hundred acres and is a shallow, grassy lake. Several smaller lakes similar in character to Spring lake are found in different parts of the town.
The Iowa and Minnesota division of the Chicago, Milwaukee and St. Paul railway crosses the western part of the town nearly north and south. The only station in the town is Rosemount, which furnishes the surrounding country with a market.
The first town meeting for the organization of Rosemount township was held May 11th, 1858, at the house of Thomas Dowd. J. H. Flannegan was chosen moderator of the meeting and James Murphy, clerk. Considerable discussion took place as to whether they should adopt the name of Rosemount or Saratoga. The name of Rosemount was finally adopted. The officers elected were: J. H. Flannegan, chairman of the board; James Murphy, clerk; William Strathern, assessor, and Andrew Keegan, justice of the peace. Under the territorial law, Thomas Clark was elected justice at the precinct election in the fall of 1856, the term being for two years, he held until the fall of 1858. The following spring he was elected town clerk, and held the office continuously, with the exception of 1865, until 1875. Andrew Keegan was elected that year and has since held the office. Following is a list of chairmen of the town board of supervisors and the years in which they served: James Murphy, 1859-60-69-70-71-2; Edward Ryan, 1861-2; C. H. Carr, 1863; Orville Woodworth, 1864; Hugh Derham, 1865-75-6-7; Elisha Blew, 1866-7-8-73; J. H. Flannegan, 1874. Dennis Mulrooney, 1878; Thomas O'Rourke, 1879-80-1.
The officers for 1881 are: Thomas O'Rourke, James McDonough and D. G. Harrington, supervisors; Andrew Keegan, clerk; William Strathern, treasurer; Thomas Clark, assessor; William Strathern and Andrew Keegan, justices of the peace, Fremont Washburn, constable.
The first justice to qualify in the town was Andrew Keegan, who took the oath of office at Mendota, then the county seat, on January 8th, 1856. He has remained in office continuously since. From 1864 to 1869 he was out of this town, but served in the place where he was located, and on his return resumed the office here.
In 1860, the total value of real and personal property in the town, as returned by the assessor, was $33,779. In 1870, the valuation was 121,324, and in 1880 it had increased to $335,457. The population of the township, as shown by the census of 1880, is 964; this includes a population of 116 in the village of Rosemount.