- November 1856 Members of Western Town Co. arrive and take possession of 320 acres
- 1857 Representatives of Dakota Land Co. take possession of 320 acres south of the Big Sioux river falls
- !858 Minnesota admitted to union leaving an area between the state border and Big Sioux River without representation. A government was formed which became known as the “Squatters Sovereignty”
- 1859 Congress establishes a post office in Sioux Falls
- March 1861 Congress establishes Dakota Territory
- August 25, 1862 Judge Amidon and son are murdered by renegade Indians forcing the abandonment of Sioux Falls on August 28, 1862
- May 5, 1865 at the request of the Territorial Legislature; Congress establishes a Military Post and reservation in Sioux Falls called Fort Dakota
- Years 1866-1873 a wave of immigrants begin arriving
- In 1870, Fort Dakota is abandoned and the reservation is open for settlement
- 1872 the Calvary Church was the first church constructed in Sioux Falls
- The 1873 population of Sioux Falls reaches 593
- In 1875 Sioux Falls brewery was established producing 250 barrels of beer
- In 1876 a Sioux Falls residence petition to incorporate is granted by Territorial Legislature
- 1877 first volunteer fire department organized
- 1878 first train arrives in Sioux Falls part of the Chicago, St. Paul, Minneapolis, and Omaha Railway Co
- 1879 Central High School completed
- 1881 Queen Bee Mill begins operations
- 1882 State Penitentiary built with funds procured by Senator Pettigrew
- 1883 the first building of what is now University of Sioux Falls built
- 1884 First contract to pump water to homes given to Sioux Falls Water Co. a private corporation from Pittsburg Pennsylvania, 5 people died from typhus because water was untreated
- 1887 Sioux Falls street railroad established by Richard Pettigrew and Samuel Tate
- 1889 South Dakota gains statehood
- 1889 The Divorce laws are carried over from territorial laws that only requires 90 day residency this brings citizens from east coast to Sioux Falls to get a quick divorce.
- 1890 Minnehaha County Court House completed on 6th street and Main Avenue
- 1893- 1895 national depression slows progress in development of Sioux Falls