When Serbia had finally been overrun, Mackensen withdrew his Germans and also some of the Austrians, these being sent north up to the Russian front, where there seemed danger of renewed activities on the part of the czar's forces. Especially threatening were the rumors that the Russians were about to make a descent on Bulgaria through Rumania, or across the Black Sea.
The Austrians along the Montenegrin front, however, remained where they were and presently they were strongly reenforced, for Austria was determined on the permanent elimination of Montenegro, as she had been determined on putting an end to the Serbian nation. Nor was this impossible, in spite of the mountainous nature of the country, if only the invaders were provided with heavy enough guns. What could be done in Serbia could also be done in Montenegro.
As far back as the middle of November, 1915, it was announced in the dispatches from Rome that Austria was assembling a force of three army corps in Herzegovina to attack Montenegro from that side. There was also available the Austrian troops already in Serbia on the eastern frontier of Montenegro, to say nothing of the Bulgarians, who so far assisted the Austrians as to take Djakova, on December 3, 1915. The whole expedition was put under the command of Von Kövess, shortly after the fall of Mitrovitza.
King Nicholas was not ignorant of what was coming. At the end of November, 1915, after Serbia's last resistance had been overcome, he issued a proclamation to his people in which he said that Montenegro would continue the fight to the bitter end, even though it was probable that she would share the fate of Serbia. The Allies, he went on to state, would make every effort to keep, not only the army, but the people as well, supplied with all that was needed to live and to resist the enemy. Supplies had always been a hard problem in that poverty-stricken little land and when the Serbian refugees began flocking in, it became an insoluble problem, unless with help from outside, which was not always forthcoming.
It was obvious that, in spite of the fact that they had assisted in a successful invasion of Serbia, the Austrians, now that they were by themselves again, were not so confident of overcoming even the Montenegrins that they could afford to undertake the campaign impulsively, for during the whole month of December, 1915, they did not press the campaign on the Montenegrin front. During this period and the first week of January, 1916, they were satisfied with more or less holding their lines, though they did advance some distance on the eastern, or Sanjak, front, capturing Plevlie, Ipek, and Bielopolie. But, as an offset to this success, the Montenegrins scored at least one victory of considerable magnitude. On December 1, 1915, the Montenegrin forces operating in southeastern Bosnia defeated the Austrians near Foca, on the Drina, seven miles across the Drina, forcing the enemy to retreat along the river toward Gorazda. A few days later the Austrians retaliated by sending an aeroplane flying over Cettinje, which dropped a number of bombs on that small city. Other aeroplanes, flying over the Montenegrin encampments, dropped circulars stating that all Serbia had been conquered, and if Montenegro made any further resistance, she would suffer the same fate. Toward the end of the month the Austrians began a heavy bombardment of Mount Lovcen and launched a strong infantry attack against it, but were repelled with considerable losses.
On December 23, 1915, the Montenegrin Government reported having inflicted a reverse on the Austrians advancing from the east. The Austrians bombarded violently in the Mojkovac sector, then attacked Touriak, in the direction of Rozai-Berane, but were thrown back. At Berane the Montenegrins assumed the offensive for a brief space, and at Bielo they drove the enemy troops back as far as Ivania.
However, these were all minor operations and the successes of the Montenegrins were not of a permanent nature. Apparently the Austrians were all this time strengthening their lines and arranging their forces for the general offensive, which they were ready to begin early in January, 1916.
On January 6, 1916, Kövess began decisive operations with a series of violent attacks on the eastern front, on the Rivers Tara, Lim, and Ibar, while at the same time the warships in the Gulf of Cattaro opened a terrific fire on Mount Lovcen.
For four days the Montenegrin troops offered a determined resistance. Berane, on the Lim, was captured by the Austrians on the 10th. On the same day the warships suddenly ceased their bombardment of Mount Lovcen and Austrian infantry swept up the mountain sides and delivered a strong attack. The handful of Montenegrins at the top were completely overwhelmed and Lovcen was captured. Some surprise was expressed among the Allies at the time that this supposedly powerful stronghold should so easily succumb, but it soon developed that the defenders were not only short of food, but they had run out of ammunition and had practically fired their last cartridges.
With Lovcen in the hands of the enemy Cettinje could no longer be held by the Montenegrins, and on January 13, 1916, it was occupied by the Austrians. The back of the Montenegrin resistance had now been broken.