Sheridan was promoted to lieutenant general on March 4, 1869. In 1870, President Grant, at Sheridan's request, sent him to observe and report on the Franco-Prussian War. As a guest of King Wilhelm I of Prussia, he was present when Emperor Napoléon III surrendered to the Germans, which was gratifying to Sheridan following his experiences with the French in Mexico. He later toured most of Europe and returned to the U.S. to report to Grant that although the Prussians were "very good brave fellows had gone into each battle with the determination to win, ... there is nothing to be learned here professionally." He criticized their handling of cavalry and likened their practices to the manner in which Meade had attempted to supervise him. However, he referred to theirs as a "perfect military system" and had a high opinion of the officer corps. His words on the French were much more harsh; he criticized the French army for not taking numerous opportunities to halt the German advance, for advancing slowly and clumsily themselves, for not taking any of the numerous good opportunities to cut the enemy's unguarded lines of communication, and for routing frequently. He remarked: "I am disgusted; all my boyhood's fancies of the soldiers of the great Napoleon have been dissipated, or else the soldiers of the "Little Corporal" have lost their elan in the pampered parade soldiers of the 'Man of Destiny'."