While this great Spring offensive from the Dunajec line was well under way, small German forces invaded the Russian province of Courland. Finding at first little resistance in the path of their unexpected advance, they took Libau and established themselves on the Dubissa-Windau line. During July the operations in Courland steadily assumed greater proportions.
Two bases for the campaign against the Russian lines of communication have thus been firmly established in the flanks of the Russian Armies west of the Vistula, both protruding far into their rear. Drives against the Dunaburg-Warsaw line from the north and the Minsk-Ivangorod line from the south will open the second year of the eastern campaign. The first year of the incessant struggle has brought the aims of the German strategy, the bagging of the Russian Armies, within sight of its realization.
III.
CAMPAIGNS OF MINOR IMPORTANCE
While the struggle in the two principal seats of war has been going on, the passing year has witnessed fighting also of secondary importance, though not less heroic, in three other fields of action: Serbia, Turkey, and the Austro-Italian frontier. Whereas Turkey joined the Teutons but three months after the beginning of hostilities, and Italy was involved only at the end of May, Serbia was one of the first nations to take the field.
Austria's campaign against the little kingdom could under no circumstances influence the events of the war, and was therefore void of any strategic importance. For this reason, but three Austrian Army corps were engaged in it.
The purpose was merely to keep the Serbians busy, and prevent them from invading Austrian soil. For the sake of the moral effect on the other Balkan States the capture of Belgrade should be attempted. In view of the strength of the Danube fortifications the operations were launched from Bosnia and resulted in the forcing of the Drina line and the capture of Valjevo on Nov. 17. The Serbian positions on the Danube having thus been flanked, the abandonment of Belgrade on Dec. 2 was a natural consequence of the Battle of Valjevo.
Misled by their successes into the belief that the Serbian army had been placed hors de combat, the Austrians advanced beyond the lines destined to constitute the object of their offensive. In the difficult mountain districts southeast of Valjevo the Serbians turned on the invaders with superior forces and defeated them. The Austrian retreat to the Drina which followed, necessitated the evacuation of Belgrade on Dec. 15. Since then, the situation on the Serbian frontier has been a deadlock, only desultory and insignificant fighting occurring for the rest of the year.
In contrast to the operations in Serbia, Turkey's campaign has direct bearing on the European war. Its chief feature, the closing of the Dardanelles, has been a serious blow to Russia. The frantic efforts of the Allies to open them are the plainest evidence of its importance.
The attempt in March to force the straits by naval power having resulted in failure, an army was landed on the west coast of Gallipoli, and after heavy fighting established itself on a line running from Eski-Hissarlik on the south coast of the peninsula to the region of Sari-Bair, on the north coast, constituting a front of approximately twenty miles, within five miles of the west coast. No progress further than this have the Allies been able to make up to the present, and the watch at the Dardanelles stands firm as yet.