Waldersee was born at Potsdam into a military and aristocratic family. After attending several cadet schools, in 1850 he was commissioned as a "Leutnant" into the Artillery Corps of the Prussian army and he soon attracted the favorable notice of his superiors. In his first major campaign, the Austro-Prussian War of 1866, he served as "aide-de-camp" to General of Artillery Prince Friedrich Karl of Prussia, with whom he was present at Königgrätz. In the course of this campaign, Count Waldersee was promoted to major and assigned to the Prussian General Staff. Thereafter, he served on the staff of X Army Corps, a new formation in the conquered kingdom of Hanover. In January 1870, he became military attaché at the Paris embassy of Prussia. At this post he was able to gather intelligence on troop strengths and other information on the French military that proved valuable in the campaigns to come.