Born in 1896, Tröger entered the army of Imperial Germany in 1915 as a Fahnenjunker (officer cadet) and served as an engineer.

In early 1943 he left the Eastern Front to take up an appointment as commander of the School for Panzer Troops, based in Germany.

[1] His new command was fighting on the Eastern Front around Kiev, in which it suffered heavy losses and further, significant, casualties were incurred in the retreat across Ukraine.

In April 1944, it was transferred to Denmark for a refit[3] and Tröger, promoted to generalleutnant[Note 1] earlier that month,[5] took over command of the 13th Panzer Division.

It had to break out and while some personnel made it to the German lines, Tröger led one element into Bulgaria and was captured by Bulgarian troops.