[1] After the First World War he settled at Isny im Allgäu, near the frontier with Bavaria and embarked upon a career as a prolific military historian and author.

Following a promotion to the rank of lieutenant colonel, he briefly joined the staff of the "Grand Prince Frederick of Baden" (8th Württemberg) No.

Moser taught at the academy until November 1909, being promoted on 24 March 1909, to the rank of colonel and made a department head in the General Staff.

With effect from 27 January 1913, Otto von Moser was appointed to the command of the 53rd Infantry Brigade (3rd Royal Württemberg), based in Ulm.

Moser was promoted to the rank of lieutenant general on 18 August 1915 and on 13 June 1916 he was transferred to the Western Front, to command the 27th Division (2nd Royal Württemberg).

On 12 March 1917 he was appointed to command the XIV Reserve Corps, fighting in the Battle of Arras and winning the Pour le Mérite, for his skill and leadership.

[2] After the war Moser lived a short distance to the east of Lake Constance, on the Ludwigshöhe estate at Isny which he had inherited through his wife.

Moser applied the royalties from his book "Die Württemberger im Weltkriege" (1927), to set up in Isny a foundation with social objectives.