Battle of Britain Pilot prototype character jug designed by William K. Harper and produced by Royal Doulton of Burslem, England, circa 1990. The Battle of Britain was a military campaign of the Second World War, in which the Royal Air Force (RAF) and the Fleet Air Arm (FAA) of the Royal Navy defended the United Kingdom against large-scale attacks by Nazi Germany's air force, the Luftwaffe. It was the first major military campaign fought entirely by air forces. The primary objective of the German forces was to compel Britain to agree to a negotiated peace settlement. Featuring a German plane being shot down in flames as its handle, this jug was designed by William Harper for a Heroes Series of character jugs, but was never put into production. Only one example is known.