In the 1930s, before the outbreak of the Second World War, the British population was somewhere between 46 million and 52 million.

Britain imported 70% of its food; this required 20 million tons of shipping a year. 50% of meat was imported, 70% of cheese and sugar, 80% of fruits, 70% of cereals and fats, 91% of butter. Of this, 1/6th of meat imports, 1/4 of butter imports and 1/2 of cheese imports came from New Zealand alone, a long ways away by shipping lanes.

 Knowing this would lead the Axis powers into hoping to starve the British population into submission, by cutting off those food supply lines. The British government began planning for wartime rationing in 1936 and massed air raids.

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