Herwarth von Bittenfeld entered the infantry with the 2nd Guards Regiment in 1811, and served through the War of Liberation (1813-15) of the Napoleonic Wars, distinguishing himself at Lützen and Paris. During the years of peace he rose slowly to high command. In the Berlin revolution of 1848, he was on duty at the royal palace as colonel of the 1st Guards.  Major-general (German: Generalmajor) in 1852, and lieutenant-general (German: Generalleutnant) in 1856, he received the grade of general of infantry and the command of the VII Corps in 1860.
In the Second Schleswig War in 1864, Herwarth von Bittenfeld succeeded to the command of the Prussians when Prince Frederick Charles of Prussia became commander-in-chief of the allies, and it was under his leadership that the Prussians forced the passage into Als following the victory over General Steinmann on 29 June, ending the war soon after.  Bittenfeld was appointed commander of the VIII Corps that autumn. On 29 June he also received the Pour le Mérite (military class) order.
In the Austro-Prussian War, Herwarth commanded the Army of the Elbe which overran Saxony and invaded Bohemia by the valley of the Elbe. His troops won the actions of Hühnerwasser and Münchengrätz, and at Königgrätz formed the right wing of the Prussian army. Herwarth himself directed the battle against the Austrian left flank.
Returning to command of the VIII Corps after the war, Herwarth von Bittenfeld became a member of the Reichstag of the North German Confederation from 1867 until 1870. He would continue to plan the defense of western Germany against a possible French offensive until July 1870. 
In 1870, during the Franco-Prussian War, Herwarth von Bittenfeld was not employed in the field, but was in charge of the scarcely less important business of organizing and forwarding all the reserves and material required for the armies in France and later overseeing prisoner of war camps when the threat of French invasion was eliminated. In 1871, his great services were recognized by promotion to the rank of field-marshal. The rest of his life was spent in retirement at Bonn, where he died in 1884. Since 1889 the 13th (1st Westphalian) Infantry carried his name.