Montezuma is a city and the county seat of Poweshiek County, Iowa, United States. The population was 1,442 at the time of the 2020 cens…Montezuma is a city and the county seat of Poweshiek County, Iowa, United States. The population was 1,442 at the time of the 2020 census. Montezuma's longitude and latitude coordinates in decimal form are 41.584737, -92.525258.