Schmidt joined the cadet corps, then entered the army in 1878. He attended the War Academy and served in the General Staff, becoming battalion commander in 1901. Three years later Schmidt was assigned chief of staff to the X Army Corps and promoted colonel in this position.
By 1908 he commanded the Fourth Guards Regiment and in 1911 in the grade of major general was appointed chief of staff to the prestigious Guards Corps; in 1912 he became deputy chief of the General Staff and in January 1914 was promoted lieutenant general.
In August 1914, Schmidt was attached to Crown Prince Wilhelm's Fifth Army at Saarbrücken as staff chief and was largely responsible for the battle of Longwy-Longuyon on August 22. The Fifth Army followed up this initial moderate victory with another at Varennes-Montfaucon on September 2/3, and advanced despite orders to stand! as far as Verdun and the Argonnes forest. Schmidt finally withdrew from Louppy to Varennes on September 12 in the wake of the German debacle at the Marne. Around Verdun and in the Argonnes forest, the struggle degenerated into trench warfare. When Crown Prince Wilhelm was given command of the Third Army in September 1915 during the fierce battles in the Champagne, Schmidt temporarily commanded the VIII Reserve Corps in brutal combat at Maison de Champagne, for which he received the order Pour le mérite.
Schmidt's career took a fateful turn on February 21, 1916, when as chief of staff of the new Army Group Crown Prince Wilhelm he unleashed the assault on Verdun. The attack was planned by Schmidt initially only against the north and northeast sectors of Verdun, but in time was broadened to include the entire area west of the Meuse River.
Schmidt's X Army Corps was dispatched to halt the Russian advance near Kovel; thereafter his Hanoverians were transferred to Alsace, where they engaged in trench warfare in relative quiet until the end of the war. Schmidt was promoted general of infantry in October 1918; in December he headed the X Army Corps at Hanover during demobilization. He retired from active service in September 1919 and died in 1936. His name will forever be linked to the tragic loss of over 300,000 German troops in the old forts of Verdun.