Max Brandt wrote:Sure - she had allies but they were not particularly active and effective. More "moral" or "paper" support.
The only two German allies of note were Italy and Japan but Italy faded and Japan came along too late in the piece and offered no support in the European theatre.
Japan was without doubt the most important ally of Germany because they fought with the British Commonwealth and Americans (although they also - at the same time - allowed Soviets to move some of their best divisions to the west from Siberia).
Hitler said once (I'm not quite sure if it was in the book of Hitler's LW adjutant Nicolaus von Below or did he said it personally to Finns on 4.6.1942 when he visited in Finland) that Finland is/was their only ally (if we count it an "ally") which didn't cause any serious troubles to Germans. If this is true then Finland is my choice in this question.
Compared to its size Finnish Army offered much more than just "moral" or "paper" support. Actually at the beginning of Barbarossa just Finnish troops where those who helped Germans in the far north and in Leningrad region (attacking to Karelian Isthmus and East Karelia). Finnish officers also teached winter warfare techniques to Germans.
The inactivity of the Finnish Army between spring 1942 and summer 1944 was a political choice because our leaders were cautious and saw that Germans were not capable of handling the war like they would have liked.