In 1916 or 1917 Schehr was conscripted into an artillery regiment and sent to serve at Neu Breisach, an important redoubt which at that time was part of Germany. Without intending it, he found himself promoted to the rank of a "sub-officer" ("Unteroffizier"). It is recorded that during one retreat he skilfully led his troops so that they avoided capture. His brother Walter Schehr was killed in action in 1916. The 1914 decision of the party leadership to vote in favour of war funding and forego criticism of the government for the duration of hostilities during the war had been contentious among party activists from the outset, and the SPD finally split over the issue of support for the war in 1917. John Schehr, like his mentor Ernst Thälmann, was one of a large number of mainly left-wing party members who moved across to the breakaway &lt;a href="Independent%20Social%20Democratic%20Party%20of%20Germany"&gt;Independent Social Democratic Party (" Unabhängige Sozialdemokratische Partei Deutschlands" / USPD)&lt;/a&gt;. After the war there was no immediate return to his skilled work, but the docks continued to function and he joined his brother Franz in work as a stevedore till 1924. In 1919 when, in its turn, the USPD), Thälmann and Schehr, were among the early recruits to the newly launched Communist Party in the wake of the so-called November revolutions. Almost all the USPD activists in the Hamburg district made the same move, which can be seen in large measure as a tribute to Ernst Thälmann's oratorical and political powers of persuasion. Schehr quickly became an energetic party activist: his brother recalled later that during the early 1920s he was out almost every evening, undertaking party work.