The wide acceptance of wrist watches by military personnel started during the trench warfare battles of WW 1. The early “wristlets” were originally seen as items worn by women only, yet their usefulness was shown before they were fully accepted by the German Army Officers involved in general procurement. The issuing authorities still considered the pocket watch to be more robust in extreme conditions.
The Germans like their British counterparts found it difficult to see the great benefit of a wrist watch over a well manufactured pocket watch.
During WW2 the German Army were issued with a specific service wrist watch. It was manufactured by at least 28 different Swiss suppliers. They mostly conformed to a standard pattern of 15 jewel shockproof movements, black dials with luminous hands. To confirm military issue the letters DH were placed on the caseback.
The use of wristwatches by Luftwaffe pilots and navigators became very widespread as accurate timings were required to assist in navigation. While more often than not it was just the pilot and navigator that were issued or used a specific, the quality that went into the production of these manufactured timepieces (Lange & Sohne, Wempe, Stowa, IWC, Hanhart and Tutima) is remarkable.
Naval personnel, including those that manned submarines (U-boats) were issued timepieces in a greater number than the equivalent British sailor. Also the Navy (Kriegsmarine) did have a number of very expensive as well as accurate chronometer watches and clocks on board the fleet vessels.