Oflag V-B was a World War II German prisoner-of-war camp for officers (Offizierlager), in operation from 1940 until 1942.

The camp was originally built as barracks for German Army infantry early in 1939 and consisted of concrete single storey buildings on a plateau north-west of the town.

It is possible that the large number or escape attempts and the close proximity to the Swiss border (only 110 km (68 mi) away) prompted the authorities to move the prisoners.

The successful escapes by Lt. Duncan and Cpt O'Sullivan were documented extensively at the time by British Intelligence.

(G) 639 (subsequently released by the British National Archives under WO/208/3307/26) with a more extensive autobiographical account written up and published in the 1950s under the title of "Underground from Posen".