I was wondering if anyone had a good idea of how extensive or sophisticated the various Great Powers intelligence networks were across the world during the 1930s prior to WW2, Axis or Allies, outside of the main warzones.
I'm particularly interested in what the later Axis powers had or knew about say the Commonwealth.
I've always assumed that they had a rough idea of the capacity of each of the nations but nothing really extensive compared to say the Soviet's capabilities during the Cold War.
The principle reason for this assumption being that the Commonwealth dominions and colonies would not have had formal diplomatic representation in each capital to any great degree, if at all. Whereas by comparison, the Soviets post War seemed to make a real effort to have quite strong embassies in most countries.
So, what did the Germans know about say Australia's military production, capacity or economy? Or indeed, Newfoundland or Rhodesia? Did Japan have any sort of good opinion on the South African navy? Did Italy keep tabs on New Zealand's coastal artillery etc etc (silly examples yes!).