A oil painting I made last month for paint class, Its a more "civilized" henge that I imagine would have fit best in the Aedui capital Bibracte.

Until around 330 BC the Aedui led the original (probably) confederated Celtic empire and are responsible for some of the Celts earliest land gains (northern Spain, southern Briton, Germany) They administrated their territories with a superb governmental structure of Kings Druids and The people a virtual duplicate of legislative, judicial and executive branches.

The people elected Druids and the Druids in turn oversaw the king. In this way a perfect social order was formed and they reaped all the benefits of such. The Aedui had professional armies, which shattered those of all contenders with ease and impunity, as well as great wealth and technology. The Aedui where one of the first few kingdoms in this period to develop paved roads. (Though the first was shockingly Ireland around the area of 200 bc)

Unfortunately rival contenders for dominion over Gaul arose from the more belligerent Arvernos tribes. The Arvernii where equally warlike, however they where suitably less democratic, the nation was led by a deified man believed to be the god Arvernos himself who held supreme command of the nation, yet was elected by a secretive council who's nature and members have escaped the grasp of history, every time the "Arvernos ascendant" died, a new replacement was elected. The civil war is thought to have started around 330 bc and had not yet concluded in the time of Caesar Augustus 300 years later. (even continuing after the Arvernii became a roman client state.) The Aedui where constantly weakened by wars in Gaul, Germany and elsewhere and their vast armies where in a dismal state when Augustus initiated his Gallic wars. Needless to say this civil war literally made the Roman Empire possible, as otherwise the Romans would have assuredly been culled at birth as Brennus had done two centuries earlier.

The Aedui had extremely positive relations with the Romans despite a few wars and they continued to exist as an independent client state of the empire (along with the Sequanii and the Arvernii among others.) These states continued to exist for the entire duration of the empire. Their ends are not known but if Jordanes comments about "Celts of gaul" arriving on field to battle the Huns at Chalons can be taken at face value, certainly more then a few of them where from Aedui.

And if Zosimus' account of the departure of the Celtic Nations from the Roman Empire can be taken at face value, the Aedui and very probably the other Gaulic states (Arvenii Sequanii ext) may very well have outlived the empire.