234 THE ROMAN CONQUESTS. [CHAP,
the part of Bavaria which lies to the northward of it, the
southern provinces of Austria, and a portion of Hungary. In
the year 15 B'.C. Drusus marched up the valley of the Adige,
and having defeated the forces of the Rhaetians near Tridentum,
the modern Trent, advanced into their land by the line of the
Brenner pass. Shortly afterwards Tiberius, approaching the
country from the opposite quarter, ascended the valley of the
Rhine, and having launched a flotilla on the lake of Constance,
succeeded in taking the enemy in the rear, and penetrating into
the upper valley of the Inn. The campaign thus begun resulted
in the complete reduction of the tribes of the eastern Alps,
together with the neighbouring districts of Vindelicia and
Noricum. The foundation of the colony of Augusta Vinde-
licorum (Augsburg) at this time had the effect of securing the
Roman conquest, and of guarding the approaches to the moun-
tain chain. These victories of the stepsons of Augustus were
celebrated by Horace in two famous odes, which glorify the
family of the Neros, and extol the difficulty of the
achievement1. The Pannonians, however, offered
a more effectual resistance to the Roman arms.
Their country was of importance to Italy because of the trade-
route which from early times had passed through it from Germany
to the head of the Adriatic2; and the facility of access which its
proximity afforded to an invading force was felt to be a source
of danger. So much was this the case, that in 6 A.D. there was
a panic in Rome, when it was reported in that city that the
Pannonians had descended on the province of Istria. Accord-
ingly, after the subjugation of the neighbouring nations which
has just been mentioned, first Agrippa, and after his death
Tiberius, invaded and ravaged their country; but the effect of
1 Hor. Od., 4. 4. 17;
Videre Raeti bella sub Alpibus
Drusum gerentem Vindelici;
and 4. 14.14;
Major Neronum mox grave proelium
Commisit immanesque Raetos
Auspiciis pepulit secundis.
2 z>. supra, p. 31.