Now let us turn to the operations in the North where Russia and Turkey clashed. The Caucasus Mountains form a barrier between the Black and the Caspian Seas but the Russian province of Transcaucasia lies to the south of the mountain range. All Transcaucasia, except for a trough to the south of the main ridge, is a wilderness of hills and peaks, through which the boundary runs. The passes are high, easily blocked by snow, and the roads were, and are, atrocious. Military operations are difficult. Germany insisted, however, that the Turks should make a demonstration in this region. The General Staff knew that Russia had none too many men equipped and ready, and any diversion which would weaken the long line in front of Warsaw would be of inestimable value to the Germans. The Caspian oilfields would also be a desirable acquisition.
Towards the end of November, 1914, the war began in the Caucasus. The chief point of concentration of the Turkish armies which were about to give battle to the Russians in the Caucasus was Erzerum, one of the most ancient and important towns in Armenia. There the 9th, 10th and 11th Turkish corps were stationed, and they had been reinforced by a division of Arabs, which had been brought from Bagdad. Two other divisions were at Trebizond, the even more ancient and famous seaport on the Black Sea, to which place they had been sent from Constantinople on transports. The total number of the Turkish forces approximated 150,000. Opposed to these General Woronzov, the Russian commander, had at his disposal slightly over 100,000 men, who had been concentrated in the vicinity of Kars, for centuries an important fortress, frequently besieged, destroyed and rebuilt. The difference in numbers, which apparently favored the Turks, was made up to a certain extent by the fact that the Russians had at their command a railway line, running in that trough between the Black
and Caspian Seas, south of the main mountain range, with a branch to Kars and Sarikamish, while the Turks were about 500 miles from their nearest railroad and had to depend entirely upon roads which were not any too good.
- The Book of History: The causes of the war. The events of 1914-1915 ...
By Viscount James Bryce Bryce, Holland Thompson, Sir William Matthew Flinders Petrie