| Place Name | Marengo |
| Place Type | City |
| ZIP Code(s) | 52301 |
| County | Iowa County |
| Area Code(s) | 319 |
| Timezone | Central Daylight Time (CDT) |
| Population (2022) | 2,841 |
| Population Growth Rate (2010-19) | -3.68% |
| Majority Ethnicity | White 95.89% |
| US Congressional District(s) | Iowa 1st |
| State House Districts | 75 |
| State Senate Districts | 38 |
| Race/Ethnicy | Percentage of Population (2021) |
|---|---|
| White | 95.89% |
| African American | 0.3% |
| Hispanic | 0.15% |
| Asian | 0.26% |
| Native American | 0% |
| Hawaiin/Pacific Islander | 3.41% |