Riverine warfare

[Nathan Ross]

Can anyone point me at any sources talking about Roman riverine warfare?

There's not a great deal out there! The best narrative source would probably be Tacitus's account of the fighting on the Rhine during the Batavian revolt of AD69 (Histories 5, 22-23 in particular) - this mentions, in passing, a captured Roman flagship being towed up the Lippe by the enemy. Annals Book 2 has some details of naval supply and transport operations during Germanicus's campaigns in Germania.

There are occasional mentions in later sources of Rhine and Danube operations - plus the pictures on Trajan's column, of course. Panegyrics from the early fourth century mention Roman river fleets in action against the Franks and Alamanni, but give few details. Ammianus Marcellinus describes some trans-river operations in the mid fourth century, although I don't recall any mention of a Rhine fleet at that point.

Passages in the Theodosian Code mention Danube river galleys (lusoriae) being repaired and maintained into the later fourth century. I don't know of any explicit literary references for the Rhine in this era, but the ships found at Mainz and reconstructed in the Mainz Ship Museum date from the 380s-90s. The general pattern was probably in use for several centuries*; these are very shallow-draught vessels, so they could presumably have been used along most of the larger subsidiary rivers as well as the Rhine itself.

*edit - the 1st-2nd century Oberstimm ships look pretty similar.