Black Hawk County (BHC) was created in 1843 by the Territorial Legislature of Iowa and attached to Delaware County for judicial, election and revenue proposes, because there were few, if any, white settlers at the time.

The Saux and Fox (Meskwaki) Indians had lived here for many years, owning the area until 1837. The county was named after the renowned Sauk Chief Black Hawk, although he never lived here.

In 1845, BHC was attached to Benton County, and in 1851 to Bushman County again for judicial, election and revenue purposes. Not until Aug. 17, 1853 did BHC have its own government.

The first permanent white settlement in Black Hawk County was started in March 1845 by William Sturgis and his brother-in-law, Erasmus D. Adams. They named their settlement Sturgis Falls. The two came to the area in search of homes and desirable waterpower. Upon arriving in the area, Sturgis and Adams were charmed by both the beauty of the area, and also by the possibility of a town site in the area.

Sturgis built a double log cabin on the banks of the Red Cedar River and broke five acres of prairie. This was considered to be the first breaking of prairie land in the county.

The name of Sturgis Falls was changed to Cedar Falls in 1851.

In 1845, two covered wagons stopped on the east bank of the Cedar River at a place known as Prairie Rapids Crossing. In these two wagons were the founders of present day Waterloo, George and Mary Hanna, along with their family. In the summer of 1846, the Virdens and the Mullans arrived, becoming the Hanna’s first neighbors. In 1851, the town was awarded a post office and a permanent title, but the name needed to be changed. Charles Mullan, who managed to secure seven signatures on a petition to get a post office, thought that the name Prairie Rapids Crossing was too cumbersome for mailing addresses. As a result, the name of the settlement was changed to Waterloo.

The area saw an influx of immigrants at the turn of the century, following the Irish in the first half of the 19th century.

New Americans from other European nations, including the Scandinavian countries and Germany, settled the countryside in the second half of the century.

In the early 20th century, there were sufficient Jewish residents to support a synagogue. In 1905, 15 charter members organized the Congregation Sons of Jacob at 613 W Fifth St.

Beginning in 1907, Croatians came to Waterloo in search of employment, especially with the Illinois Central Railroad. An estimated 500 immigrants were the Balkan representation in the early 20th century.

Newcomers from Greece settled on the east and west sides of the city, although most lived on the west side. Although a few Greeks briefly stayed in Waterloo in the late 19th century, it was not until the early 20th century that they settled permanently in significant numbers.

African Americans did not come in substantial numbers until 1911.