During the truce of 1849 he qualified as Privatdocent at Kiel, but on the fresh outbreak of war he returned to the troops and was promoted to the rank of senior surgeon.

When the Franco-Prussian War broke out in 1870, he was appointed surgeon-general to the army, and afterwards consulting surgeon at the great military hospital near Berlin.

[1] In 1872 Esmarch married Princess Caroline Christiane Auguste Emilie Henriette Elisabeth of Schleswig-Holstein-Sonderburg-Augustenburg (1833–1917), aunt of Empress Augusta Viktoria.

His Handbuch der kriegschirurgischen Technik was written for a prize offered by the empress Augusta, on the occasion of the Vienna Exhibition of 1877, for the best handbook for the battlefield of surgical appliances and operations.

The latter is the substance of a course of lectures delivered by him in 1881 to a Samaritan School, the first of the kind in Germany, founded by Esmarch in 1881, in imitation of the St John Ambulance classes which had been organized in England in 1878.