Pioneer (military)

A pioneer (/ˌpaɪ.əˈnɪər/) is a soldier employed to perform engineering and construction tasks. The term is in principle similar to sapper.

Pioneers were originally part of the artillery branch of European armies. Subsequently, they formed part of the engineering branch, the logistic branch, part of the infantry; or even comprised a branch in their own right.

Historically, the primary role of pioneer units was to assist other arms in tasks such as the construction of field fortifications, military camps, bridges and roads. Prior to and during the First World War, pioneers were often engaged in the construction and repair of military railways.

During the 20th century, British Commonwealth military forces came to distinguish between small units of "assault pioneers" belonging to infantry regiments and separate pioneer units (as in the former Royal Pioneer Corps). The United States Marine Corps has sometimes organized its sappers into "Pioneer Battalions".

The word pioneer is originally from France. The word (French: pionnier) was borrowed into English, from Old French pionnier, which meant a "foot soldier", from the root 'peon' recorded in 1523. It was used in a military sense as early as 1626–1627. In the late 18th century, Captain George Smith defined the term as:

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