Summons sent to Rudolf Jakob Loo to report for active duty for construction of the Peter the Great’s Naval Fortress.

A national defence force member, grade 2, living in Nehatu rural municipality, Jakob was to report for duty on 5 September 1916.

The construction of Peter the Great’s Naval Fortress started in 1911 and the work continued through the World War, although at a slower pace. The workforce consisted of military people, locals, workers hired from Russia and German prisoners of war. The vicinity of the Tallinn military port along with the Peter the Great’s Naval Fortress was in the jurisdiction of the imperial Baltic Fleet and belonged to the Russian imperial army’s 1st Army Corps.