The E.II was essentially a Fokker E.I with the 75 kW (100 hp) Oberursel U.I 9-cylinder rotary engine, a close copy of the French Gnôme Monosoupape rotary of the same power output, in place of the E.I's 60 kW (80 hp) Oberursel U.0, but whereas the E.I was simply a M.5K with a 7.92 mm (.312 in) machine gun bolted to it, the E.II was designed with the weapon system integrated with its airframe.
It was during these demonstrations, only one week before any kills would be achieved in the Eindecker type, that Fokker himself attempted to engage an enemy aircraft but he was unable to find a target.
The major difference between the types was a reduced wingspan on the E.II, intended to increase speed, but handling and climbing performance suffered.
In total, Fokker production figures state that 49 E.IIs were built and 45 of these had been delivered to the Western Front Fliegertruppe by December 1915 (Luftstreitkräfte from October 1916 onwards) at which time production switched to the main Eindecker variant, the Fokker E.III, which used the same 75 kW (100 hp) Oberursel U.I engine.
Some E.IIs under production were completed as E.IIIs and numerous E.IIs returned to Fokker's factory for repair were upgraded to E.III specification.