Battle of Alesia
Caesar engaged in the Gallic Wars (58–50 BC), which led to his conquest of Gaul beyond Gallia Narbonensis. When the Helvetii, a federation of tribes from what is now Switzerland, planned a migration to the Atlantic coast through Gaul, Caesar went to Geneva and forbade the Helvetii to move into Gaul. While he went to Gallia Cisalpina to collect three other legions, the Helvetii attacked the territories of the Aedui, Ambarri, and Allobroges, three Gallic tribes, which called for Caesar’s help. Caesar and his Gallic allies defeated the Helvetii. The Gallic tribes then asked for Caesar to intervene against an invasion by the Suebi, a Germanic tribe. Caesar defeated the Suebi. In 57 BC he intervened in intra-Gallic conflicts and marched on the Belgae of northern Gaul. From then on he conquered the Gallic peoples one by one. His successes in Gaul brought Caesar political prestige in Rome and great wealth through the spoils of wars and the sale of war captives as slaves.
Galley
From around 1450, three major naval powers established a dominance over different parts of the Mediterranean using galleys as their primary weapons at sea: the Ottomans in the east, Venice in the center and Habsburg Spain in the west. The core of their fleets were concentrated in the three major, wholly dependable naval bases in the Mediterranean: Constantinople, Venice and Barcelona. Naval warfare in the 16th century Mediterranean was fought mostly on a smaller scale, with raiding and minor actions dominating. Only three truly major fleet engagements were actually fought in the 16th century: the battles of Preveza in 1538, Djerba in 1560 and Lepanto in 1571. Lepanto became the last large all-galley battle ever, and was also one of the largest battle in terms of participants anywhere in early modern Europe before the Napoleonic Wars.