The Batavians were loyal allies of Rome throughout their wars in Germania and remained loyal even after the Varian Disaster and the revolt of 9 AD. Augustus had a personal bodyguard of Batavians which was disbanded in the panic which followed the news of Arminius' uprising, but units of Batavians served loyally in the Roman army throughout its history. The exception was the great Batavian Uprising of 69-70 AD when the Batavian chieftain and commander who we know by the Roman name of "Julius Civilis" had some success against Rome initially. The revolt was eventually crushed by Quintus Petillius Cerialis.

The most conspicuously brave of all the German tribes in Gaul, the Batavi, hold little of the river- bank, but do hold the Rhine island. They were once a section of the Chatti, and on the occasion of a civil war they migrated to their present home - destined there to become a part of the Roman empire. But they still retain an honourable privilege in token of their ancient alliance with us. They are not subjected to the indignity of tribute or ground down by the tax-gatherer. Free from imposts and special levies, and reserved for employment in battle, they are like weapons and armour - 'only to be used in war'.

Tacitus, Germania, 29.

The Meuse rises from Mount Le Vosge, which is in the territories of the Lingones; and, having received a branch of the Rhine, which is called the Waal, forms the island of the Batavi, and not more than eighty miles from it it falls into the ocean.

Caesar, The Gallic War, Bk IV, Ch 10.

The island of the Batavi was the appointed rendezvous, because of its easy landing-places, and its convenience for receiving the army and carrying the war across the river. For the Rhine after flowing continuously in a single channel or encircling merely insignificant islands, divides itself, so to say, where the Batavian territory begins, into two rivers, retaining its name and the rapidity of its course in the stream which washes Germany , till it mingles with the ocean.

Tacitus, The Annals, Bk II, Ch 6 (On Germanicus' preparations for his Germanic campaign)