Cedar Rapids is a city in Linn County, Iowa, United States, and its county seat. The population was 137,710 at the 2020 census, making it the second-most populous city in Iowa. The city lies on both banks of the Cedar River, 20 miles (32 km) north of Iowa City and 128 miles (206 km) northeast of Des Moines, the state's capital.

Cedar Rapids is the economic hub of Eastern Iowa, located at the core of the Interstate 380 corridor. The population of the three-county Cedar Rapids metropolitan area, which includes the nearby cities of Marion and Hiawatha, was 276,520 in 2020. The Cedar Rapids metropolitan area is also part of a combined statistical area with the Iowa City metropolitan area.

The location of present-day Cedar Rapids was in the territory of the Meskwaki and Sauk peoples at the time of European American settlement.

The first settler on the site of the future city was Osgood Shepherd, who built a log cabin (which he called a tavern) in 1837 or 1838 next to the Cedar River (then known as the Red Cedar) at what is now the corner of First Avenue and First Street Northeast. Shepherd was a squatter who claimed the land without legal title and also a reputed ne'er-do-well, who, if he was not a horse thief himself, definitely consorted with them. Early on, it appears that he "jumped the claim" of another squatter, Wilbert Stone, who had built a cabin and platted out a town, some distance south of Shepherd's cabin, that he called Columbus. Shepherd drove Stone across the river, claiming that Stone had built his cabin on Shepherd's land, then sold Stone's cabin to a buyer named Hull. Shepherd later tried the same tactic with perhaps the first settler on the west side of the river, Robert Ellis, but Ellis happened to be chopping wood at the time and warned that someone would be dead if Shepherd did not retreat.

The true founders of the city were George Greene, Nicholas Brown, and a few others. Brown had experience as a miller and Greene had surveyed much of eastern Iowa, so both saw the value of the spot Shepherd had claimed. It was right next to the rapids—a prime spot to build a mill—the last set of rapids on the river before the Cedar fed into the Iowa River, meaning that goods milled on the spot could be carried by boat down river to the Mississippi. In 1841, they formed a partnership that bought out Shepherd's claim and platted out a town they called Rapids City. Brown immediately constructed a primitive dam and then built the town's first mill. His crude dam soon washed away, prompting Greene to induce Alexander Ely, an engineer from Michigan, to build a proper dam that created a mill race capable of powering several mills.

At this time, the city was confined to the east side of the river. The west bank soon contained a village named Kingston for resident David King who early on operated a rope ferry across the river.

The town was formally incorporated by the Iowa State Legislature on January 15, 1849 as Cedar Rapids, named for the rapids in the Cedar River (the river itself was named for the large number of red cedar trees that grew along its banks). The population was less than 400.

During the 1850s, Cedar Rapids grew in size, and it was during this decade that the Czech population became substantial; when the town was reincorporated in 1856, a quarter of its roughly 1,600 inhabitants were Czech immigrants. The availability of cheap land in the new state of Iowa happened to coincide with the Revolutions of 1848 in the Austrian Empire that caused a large number of Czechs to flee their homeland and emigrate to the U.S. In 1851, the institution that eventually become Coe College was founded. In the same decade, there were attempts by local leaders to improve the city's access to distant markets, first through purchase of a steamboat (aptly named Cedar Rapids) and ultimately through investment in a railroad. The first locomotive rolled into town on June 15, 1859.