Hiawatha, IA has a population of 7,160 and is the 5,100th largest city in the United States. The population density is 1,548 per sq mi which is 2733% higher than the Iowa average and 1608% higher than the national average. The median age in Hiawatha is 36 which is approximately 5% lower than the Iowa average of 38. In Hiawatha, 56% of the population over 15 years of age are married, 95% speak English and 1% speak Spanish. 75% of Hiawatha residents were born in Iowa, 22% were born out of state, 0% were born outside of the United States and 3% were foreign born.