Nauvoo, IL has a population of 1,292 and is the 13,587th largest city in the United States. The population density is 382 per sq mi which is 72% higher than the Illinois average and 321% higher than the national average. The median age in Nauvoo is 47 which is approximately 24% higher than the Illinois average of 37. In Nauvoo, 69% of the population over 15 years of age are married, 96% speak English and 2% speak Spanish. 28% of Nauvoo residents were born in Illinois, 70% were born out of state, 1% were born outside of the United States and 2% were foreign born.