Nashua is a city in Chickasaw County and Floyd County, Iowa. As of the 2020 census, the city's population was 1,551 a 6.7% decrease from 2010. The famed Little Brown Church featured in the song "The Church in the Wildwood" is located in Nashua.

Chickasaw County is a county located in the U.S. state of Iowa. As of the 2020 census, the population was 12,012. Its county seat is New Hampton. The county was named for the southern Indian Nation whose chief was Bradford.