In 1915 -1918, during German occupation Kaunas was the seat of several military Feldpost offices attached individually at various times to such important commands as Commander-in-Chief East (Oberbefehlshaber Ost), his administrative section, Commander of Tenth Army, also the stationary Feldpoststation 209 and, uniquely, the fortress postal system (Festungspost).
Of special relevance to immediate post-war development was the civilian post office Kowno, established within the structure of Postgebiet Ob.-Ost and opened on January 15, 1916. It took over the old spacious czarist-period P.O.building, which in addition now housed the supervisory administration of the entire Postgebiet.
During the German withdrawal from the East the civilian post offices ceased functioning in late December 1918. The P.O.Kowno closed down on December 26, 1918.
In Lithuania, the exiting German administration had notified in advance interim Lithuanian authorities of its general intention to close the P.O.s, but specific hand-overs proceeded at a very short notice, if any.
For Kaunas, the incoming Lithuanian Pašto Valdyba had offered the postmaster’s position to Feliksas Damijonaitis, writing to him on December 10 and again on 18. On December 27, departing German staff from the Kowno P.O. officially handed over to him a bag containing 22 registered letters. He recalls that on December 26, he received from a representative of Pašto Valdyba in Vilnius an advance of 1000 Auksinai and a quantity of postal stamps. But the German personnel (because still balancing their books for the entire Postgebiet) refused to hand over the building and Feliksas Damijonaitis had to search and set up the Lithuanian post office of Kaunas elsewhere in a very modest manner. As a result, it is not clear when the Kaunas P.O. did in fact commence its work, though the date of December 27, 1918 cannot be ruled out altogether.
[For a more detailed examination of the circumstances see an article /in Lithuanian/ by Vytautas Doniela, “Paštai Kaune 1915 – 1918 metais’ in Journal of the “Lithuania” Philatelic Society, No. 234 (2005). This article also gives an account of the complex Feldpost facilities in Kaunas in World War One.]
As the recollections of specific dates by contemporaries may not be entirely faultless and do indeeed sometimes conflict, there is no absolute certainty about the earliest stock of stamps available at Kaunas. On the whole, parallel with Gardinas (Grodno) etc., at the start Kaunas seems to have had the 10 and 15 values of the First Vilnius Issue and the 20 and 30 values of the Second Vilnius Issue, though it is possible that the First Vilnius stamps were received earlier. It must be recalled that these events took place within just one week in unsettled surroundings.
Having no formal postmarker, for cancelling the Lithuanian P.O. at Kaunas made use of a makeshift rubber one-liner “Kauno paštas” applied in violet, often with rather faint results.
The remaining values of the Second Vilnius Issue, namely, 10, 15, 40, 50, certainly arrived later.
As the Pašto Valdyba had made advance arrangements to procure some basic tools, the first formal calendar-type postmarker was put into use at Kaunas as early as January 3, 1919.
A work-in-progress Register of mail bearing “Kauno paštas”:
[27. XII. 1918] (?) cover to Pašto Valdyba in Vilnius, Vilnius II 30 [colln.Lapas]
No date but transit Feldpost 4. I. 19, to Königsberg, Vilnius II 30 x4 [formerly Norton]
No date, cover Feinberg to Königsberg, Vilnius II 30 x2 [colln. Bubnys]
No date, cover to Königsberg, Vilnius II 30 x2 [colln. Lapas]
No date, cover to Spandau, Vilnius I 10, 15, Vilnius II 20, 30 [colln. Doniela]
No date, cover to Berlin, Vilnius I 10, 15, Vilnius II 20, 30 [colln. ?]
No date, philatelic cover addressed not posted, Vilnius II 10, 20, 30, 40, 50 [colln. ?]