Though Germany had promised its support (on July 5) to Austria-Hungary in whatever actions it took concerning the Serbian crisis, it seems that the Austro-Hungarians took full advantage of this blank check by not even keeping its ally informed of its intentions or actions. This course began on July 28th, when both Berlin (Germany) and Belgrade (Serbia) were informed of Austria-Hungary’s declaration of war against Serbia at about the same time.
Part of the reason for Germany’s promise of July 5 was to make sure that its support for its junior partner in the alliance was publicly displayed. Austria-Hungary could not appear too weak, or Germany would lose its only neighboring friend. The Kaiser had originally taken the position that the time had come for Serbia to finally punish and swallow up Serbia, but with the Russian’s taking up a firm position to counter Germany’s, and with Serbia acting submissive, the Kaiser had begun to reconsider.
Austria-Hungary’s early declaration of war against Serbia was therefore intended to prevent just such a softening of resolve from Germany, and indeed, the German’s immediately complained to the Austro-Hungarian government via diplomatic channels, saying that ‘the Austro-Hungarian government “has left us in the dark concerning its intentions, despite repeated interrogations,” and that is declaration 0f war had put Germany in “an extraordinarily difficult position” that could cause it to “incur the odium of having been responsible for a world war.” ‘
~G.J. Meyer, A World Undone: The Story of the Great War, 1914-1918 (New York: Delacorte Press, 2006), 49-54.
July 28th was therefore also the day when Germany began to urge Austria-Hungary to limit its war plans . . . to stop in the Serbian capital of Belgrade after it had invaded, and negotiate peace from this position of strength. Coincidentally, Austria-Hungarian artillery had begun to shell Belgrade from across the border early that day.
This day also included an incredible misunderstanding as well, as representatives from Russia and Austria-Hungary met to discuss the mounting crisis. The Austro-Hungarians left the meeting believing that they had made it clear that while they would not negotiate with Serbia, they were prepared to do so with Russia. The Russians, on the other hand, left the meeting believing that Austria-Hungary would not negotiate with either Serbia or Russia. Russian minister Sergei Sazonov knew that the German’s would have to mobilize their army also if Russia continued in that direction, but with Austria-Hungary taking such an intractably aggressive stance, what else could Russia do?