He came immediately after entering as a student at the recently established Royal Danish Defence College,[1] from which he resigned 4 years later as First Lieutenant and Deputy in the General Staff, but did not come into service with it until after going through the schools of the infantry and cavalry.

Thus he did not come into the fire until the following year; he then became Chief of Staff to General Olaf Rye and took part in the battles at Kolding, Almind - Dons , Vejle and Aarhus, which during the whole retreat in Jutland he made so much profit that in June he was given the rank of lieutenant colonel.

13,[4][1] whose corps position at Selk and Jagel was attacked by the Austrians on 3 February, while it was handed over to the division, as the evacuation was to be launched 2 days later to form the army's rear guard.

Steinmann performed this duty with tirelessness and zeal, and he watched with great care the Battle of Sankelmark, where he was wounded in the leg by a piece of grenade.

[1] The Army received this appointment consistently with sympathy, and the day-command issued by him made a good impression, but then by 12 July Armistice negotiations were initiated, he was only given the opportunity to make very careful arrangements for Funen's defense.

[4] When it proved difficult to get the post of commanding general in Jutland occupied, Steinmann was asked to take it over again in December 1877, and he remained there until he was dismissed due to age in 1882, while at the same time being placed à la suite.

Steinmann then retired to Tybjerggård, where he often gathered a larger circle of older and younger comrades around him and with lively interest continued to follow the development of events.

He didn't have a magnificent nature, but was a brave soldier and a very conscientious, punctual superior who was carefully within the Army's administrative regulations and had a clear eye for terrain and fencing conditions.