Scorpiomikey
We could get very picky and add alot of countries here, but the UK and Belgium were the only ones that purchased the RE8 for their own use.
Some of our Aussie friends may get uptight about this, but until 1931 Australia was legally considered a colony of the UK, and their forces during WWI were supplied from British stocks. The Australian Flying Corps was formed as part of the armed forces of the British Empire via the Imperial Conference of 1911 and was part of the First Australian Imperial Force, i.e. the Australian Army until 1919. Australia was the only colony to create the forces authorized by that conference. Even though they were raised and officered by Australians they fell under the overall British Imperial Command and therefore they were part of the UK at that time.
Estonia and the Soviet Union obtained RE8's through the 1919 intervention by the British against the newly formed Soviet Union. We should then include the White Russian forces as operating them (through British stocks) and also Poland (captured a Soviet one in the 1920-21 War). The Soviet aircraft were captured from the White Russians and the British expeditionary force. I am not sure where Estonia got theirs, but I would assume that they were also among the 100 the Britsh initially operated during that operation and were left behind.
The question of captured aircraft being operated can take many of our questions in different directions, in this case the ownership of the aircraft were either British or Belgium, nobody else purchased any. I am sorry that it took your thoughts away from the subject I had in mind, Wikipedia can do that.
Mike T.
Edit: Check Wikipedia's entry for the Gotha V shows only German Imperial use. Poland operated a few until the late 1920's but they aren't listed. they received them from stocks of aircraft left over from WWI.
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