Julius Caesar in Gallic Wars tells us ( 1. 51 ) that Ariovistus had gathered an army from a wide region of Germany, but especially the Harudes, Marcomanni, Triboci, Vangiones, Nemetes and Sedusii.

The Romans defeat Ariovistus, and Caesar is overjoyed to find and rescue C. Valerius Procillus, the envoy who had been captured earlier by Ariovistus.

Upper Germania was occupied by Gaulish tribes including the Helvetii, Sequani, Leuci, and Treveri, and, on the north bank of the middle Rhine, the remnant of the Germanic troops that had attempted to take Vesontio under Ariovistus, but who were defeated by Caesar in 58 BC.

From a strategic point of view, the Agri Decumates, or region between the Rhine and Danube, offers a bulge in the line between the Celts and the Germanics, which the Germanics had tried to exploit under Ariovistus.

Where Caesar had described burning the wretched brush hovels of the Suebi who had come to fight for Ariovistus, the Chatti and the Alamanni now lived in comfortable Romanized villages around the limes.

When Caesar inquired of his prisoners, wherefore Ariovistus did not come to an engagement, he discovered this to be the reasonthat among the Germans it was the custom for their matrons to pronounce from lots and divination whether it were expedient that the battle should be engaged in or not ; that they had said, " that it was not the will of heaven that the Germans should conquer, if they engaged in battle before the new moon.

It is likely that Ariovistus ' authority only extended over those Germans who had settled in Gaul.

In 59 BC, while Julius Caesar was consul, Ariovistus had been recognised as " king and friend " by the Roman Senate.

Caesar therefore sent his ambassadors back to Ariovistus with his demands: that he bring no more of his people across the Rhine, and that he and his allies restore the hostages they had taken from the Aedui and undertake not to make war against them.

He pointed out that Ariovistus was a friend to Rome and that the Romans had a prior interest, which they certainly would enforce.

Apparently Ariovistus had learned of the Roman presence there because he stopped marching and waited.

Ariovistus sent ambassadors to Caesar agreeing, because Caesar had come to him, to a conference.

Ariovistus now took the tack of claiming the Aedui had attacked him, rather than vice versa.

Caesar reports that Ariovistus stated that " he was not so uncivilized nor so ignorant of affairs, as not to know that the Aedui in the very last war with the Allobroges had neither rendered assistance to the Romans, nor received any from the Roman people in the struggles which the Aedui had been maintaining with him and with the Sequani.

However, it is evident that there was a more mundane reason for Ariovistus declining battle: he had Caesar surrounded.

Ariovistus had Caesar under siege and hoped to starve him out.

Caesar had just settled the last of them among the Aedui when the campaign against Ariovistus began.

In the early empire the same Germanic tribes that had fought for Ariovistus appeared on both sides of the Rhine in Alsace.

According to Caesar's Celtic informants, Ariovistus had appeared as a leader of Germani who had settled in the land of the Aedui ( upper Loire ) following the assistance of a vanguard of 15, 000 at the Battle of Admagetobriga in 61 BC.

Moreover, he omits mention of what happened to the Vangiones and other tribes that had crossed the Rhine ( if they did ) after the defeat of Ariovistus.

Furthermore, it is known that the druids held high functions since Diviciacus came to Rome to plead the case of the Aedui during the Germanic invasion led by Ariovistus on the account of the Sequani.

By the time of Julius Caesar, a group of Germans led by the Suebian chieftain Ariovistus were expanding into Gaul, until stopped by Caesar at the battle of Vosges.

Caesar takes military action against Ariovistus for two reasons: first, because the Aedui are allies of Rome, and second, because Caesar wanted to stop the flow of Germans from across the Rhine into Gaul.

* The Helvetii and other peoples under Ariovistus invade Gaul.

This demand ' concerned ' Rome because if the Sequani conceded, Ariovistus would be in a position to take all of the Sequani land and attack the rest of Gaul.

Ariovistus was probably picked from among the generals to lead an army group into Gaul, as seers were generally used for that purpose.

They threw in their lot with Ariovistus in his bid of 58 BC to invade Gaul through the Doubs river valley and lost to Julius Caesar in a battle probably near Belfort.

Alsace-Lorraine is covered mainly in the section on Gaul and describes the region as it must have been before Ariovistus led his expedition across the Rhine.

In return, Ariovistus was promised land grants in Gaul, although exactly where is not certain.

" But a worse thing had befallen the victorious Sequani than the vanquished Aedui, for Ariovistus, the king of the Germans, had settled in their territories, and had seized upon a third of their land, which was the best in the whole of Gaul, and was now ordering them to depart from another third part, because a few months previously 24, 000 men of the Harudes had come to him, for whom room and settlements must be provided.

His first known works are Bellum Sequanicum, a poem on Julius Caesar's campaign against Ariovistus, and some satires ; these should not be confused with the Menippean Satires of the other Varro, of which some 600 fragments survive.

" The Sequani also habitually supported the Germans in their previous frequent expeditions across the river, which shows that Ariovistus ’ subsequent devastation of Sequani lands represented a new policy.

The location of the final battle between the Aedui and their enemies, which Caesar names as the Battle of Magetobriga, remains unknown, but Ariovistus ’ 15, 000 men turned the tide, and the Aedui became tributary to the Sequani.

Ariovistus refused the summons, on the grounds that if Caesar wanted to speak to him, he should come to him ; besides, he was not prepared to enter Caesar's territory without his army, which it would be impractical and expensive to gather.

In 58 BC, Caesar defeated the Germanic tribe of the Suebi, which was led by Ariovistus.

Perhaps Strabo was relying on an earlier account, which depicts Alsace before Ariovistus, and yet he knew of the defeat of Varus.

* Ariovistus, German king

The Arverni and Sequani decide to get help in their struggle from German mercenaries from across the Rhine, led by a king named Ariovistus.

The Sequani defeated and massacred the Haedui at the Battle of Magetobriga, with the help of the Arverni tribe and the German Suebi tribe under the Germanic king Ariovistus.

The name Equestris was applied after Caesar mounted legionaries from the Tenth on horses as ruse to parley with the German King Ariovistus in 58 BC.

The Tenth gained its name Equestris during the Gallic War, when Caesar mounted the Tenth temporarily so that he could have his favored troops as a bodyguard, yet still conform to an agreement made between him and the German King Ariovistus.