All of these have different languages, customs, and laws. The Celts are separated from the Aquitani by the river Garonne, from the Belgae by the Marne and Seine.
The Belgae are bravest of three peoples, being farthest removed from the highly developed civilization of the Roman Province, least often visited by merchants with enervating luxuries for sale, and nearest to the Germans across the Rhine, with whom they are continually at war. For the same reason the Helvetii are braver than the rest of the Celts; they are in almost daily conflict with the Germans, either trying to keep them out of Switzerland or themselves invading Germany.
The region occupied by the Celts, which has one frontier facing north, is bounded by the Rhone, the Garonne, the Atlantic Ocean, and the country of the Belgae; the part of it inhabited by the Sequani and the Helvetii also touches the Rhine.
The Belgic territory, facing north and east, runs from the northern frontier of the Celts to the lower Rhine. Aquitania is bounded by the Garonne, the Pyrenees, and the part of the Atlantic coast nearest Spain; it faces north-west.
2. The foremost man among the Helvetii, in rank and wealth, was Orgetorix. In the consulship of Marcus Messala and Marcus Piso (61B.C.) he was induced by the hope of obtaining royal power to organize a conspiracy of nobleman, and persuaded his country-men to emigrate en masse, telling them that they were the best fighters in Gaul and could very easily conquer the whole country. They listened the more readily to his proposal because their territory is completely hemmed in by natural barriers – on one side by the Rhine, a very broad and deep river, which is the frontier between them and the Germans; on another side by the high mountain range of the Jura, between them and the Sequani; on a third, by the lake of Geneva and the Rhone, which form the boundary between the Helvetii and the Roman Province. These obstacles restricted their movement and made it more difficult to attack their neighbors; and as they are a warlike people they greatly resented this restraint. Considering their large population, military prestige, and reputation for bravely, they felt that their territory－only two hundred and twenty miles long, one hundred and sixty-five wide-was unduly small.
3. Impelled by this feeling and by the influence of Orgetorix, they determined to prepare for emigration by buying up all the draught cattle and wagons they could, sowing as much land as possible in order to secure an adequate supply of corn for the journey, and establishing peaceful and friendly relations with their neighbors.
They thought that two years would suffice for completing these preparations, and passed a formal resolution fixing their departure for the third year.
Orgetorix was put in charge of the arrangements and undertook a mission to the neighboring peoples, in the course of which he persuaded a sequanian named Casticus, whose father Catamantaloedis had been king of his tribe for many years and had been honored by the Senate with the title of Friends of the Roman people to seize the royal power which his father had held before him. He also induced the Aeduan Dumnorix, Diviciacus, brother, who at that time held the chief magistracy of his tribe and enjoyed great popularity, to make a similar attempt, and gave him his daughter in marriage. Orgetorix convinced them that these schemes were quite easy of achievement by telling them that he intended to usurp the sovereignty of his own state, which he said was beyond question the most powerful in Gaul, and that he would use his wealth and military strength to secure them the possession of their thrones.
His arguments proved effective. The three men swore an oath of mutual loyalty, hoping that once they had made themselves kings the great power of the warlike peoples they ruled would enable them to get control of all Gaul.
The Conquest of Gaul (Penguin Classics)