Labour battalions have been a form of alternative service or unfree labour in various countries in lieu of or resembling regular military service. In some cases they were the result of some kind of discriminative segregation of the population, while in some others they have been a conscious choice.
In some countries labour battalions were created from part of population which for various reasons were not suitable for regular military service, often because this population was considered "undesirable" or "unreliable", e.g., political enemies, population of occupied territories or "lower races".
Examples include labour battalions in the late Ottoman Empire and early Turkish Republic, labour service in Hungary during World War II, as well as labour battalions in other territories held by Nazi Germany and its allies (see also "Hiwi".).
In some countries labour battalions are a form of alternative conscription for people who cannot join military service for various reasons, e.g., due to bad health or being conscientious objectors to any forms of violence.
Until the last days of the Soviet Union with obligatory military duty in the state, men deemed unfit to regular military duty, as well as many able-bodied ones, were assigned to construction battalions (стройбаты) of the Soviet Army .