LaPaz is a town in North Township, Marshall County, Indiana, United States. The population was 475 at the 2020 census, down from 561 in 2010. The town was founded in 1873 and was named for La Paz, Bolivia. At the time of its founding, it was served by the Chicago branch of the Baltimore and Ohio Railroad, now CSX. The B&O named a coach L…LaPaz is a town in North Township, Marshall County, Indiana, United States. The population was 475 at the 2020 census, down from 561 in 2010. The town was founded in 1873 and was named for La Paz, Bolivia. At the time of its founding, it was served by the Chicago branch of the Baltimore and Ohio Railroad, now CSX. The B&O named a coach La Paz in 1949 to honor the town.