Serbia was invaded by the Austrians and Germans in October, 1915, and
the campaign was conducted by the Central Powers with characteristic
ruthlessness. Rumania fought gamely, but eventually had to yield under
the Treaty of Bucharest, and Montenegro was also quickly disposed of.
The Austrians were thus established in Northern Albania and were led
to take up an offensive in Trentino. This was begun in May, 1916,
and honours were first with one side and then with the other until
in October, 1917, with the help of the Germans, Austria forced the
Italians to retreat to the line of the Piave. British and French
troops were sent to the assistance of Italy, and the invaders were
disastrously defeated, being swept back across the Piave.
The morale of the Austrian troops, except when aided by the Germans,
was never satisfactory, and the condition of her home affairs became
worse as the war progressed. The Emperor Francis Joseph died in
November, 1916, and he was succeeded by the Emperor Karl, who was
suspected of having strong leanings in the direction of peace. The food
problem in Austria also became a very difficult one, and this, combined
with industrial and political unrest, tended to undermine the Empire’s
military efficiency until eventually the operations against Italy came
to be regarded as of secondary importance, and overtures were made for
peace.
The Allies recognised the Czeko-Slovaks as a separate nation; the
Croatians recognised themselves; and a promise was made that Bohemia
should be divided into national districts. Following unsuccessful
attempts to obtain peace through President Wilson, the Austrians
acknowledged the inevitable and asked for peace on October 27th, 1918.
Bulgaria had surrendered on September 29th.