Field post office
A Field Post Office (FPO) is a post office set up during time of war or when a military unit is on manoeuvres. It is set up 'in the field', hence the name, however, FPOs may be on land or at sea. Their use pre-dates the introduction of postage stamps.
In the United States a close equivalent is the Army Post Offices (APOs), the Air Force Post Offices (AFPOs) and the Fleet Post Offices (FPO in the U.S.).
In Hungary the head FPO is known as the tabori fopostahivatal while a normal FPO is an tabori postahivatal.
Equivalent terms are in use in most countries with Field Post Offices.
Field Post Offices have special cancels and their mail is eagerly collected by philatelists, but the cancels are sometimes anonymised so that the place of posting is not revealed and this presents collectors with a challenge.
See also 
- History of the BFPO
- British Postal Museum & Archive Crimea FPO cancellations 1854-57.
- Ask Phil Philatelic Glossary.
Further reading 
- Crouch, G. and Hill, N. British Army Field Post Offices 1939-1950: Locations and Assignments, 1951.
- King, Christopher. "The Prussian Field Post-Relais in Denmark 1864: Mail in Denmark Handled by the Static Prussian Field Post Offices" in The Posthorn, Scandinavia Collectors Club, November 2007. Download link
- Lowe, Robson. Indian Field Post Offices 1903-04, The Aden-Yemeni Boundary Commission, The Somaliland Field Force, Robson Lowe, 1979. ISBN 0-85397-107-2.
- Wagner, Ryszard. History of the Polish Army Postal Service, Middle East and Italy 1940-1948, Caldra House Limited, 1992.