Isopods are distributed throughout North America. Some are native, such as one aquatic species that is limited to a single location.

Armadillidium vulgare is native to Europe but has been widely introduced to North America. It is found in grasslands and woody shrubland. This and other exotic isopods arrived in soil ballast and with plants brought by European immigrants.

The species name “vulgare” translates as “common” and refers to this species’ widespread distribution in Europe.