Dura Europos. https://www.persee.fr/doc/syria_0039-7946_1986_num_63_1_6923  

Civilis did not possess a native Batavian navy. The vessels he commanded were captured Roman ships. Earlier in the rebellion, the Batavians had ambushed and captured Roman river flotillas (Classis Germanica) based along the Rhine, as well as light coastal vessels operating in the North Sea. To pad his numbers, Civilis added local transport boats, skiffs, and canoes. Tacitus notes in this quote you shared that he rigged these captured craft and boats with particoloured plaids (traditional Germanic woven cloaks) as improvised sails, creating a colorful visual display.

Some phrases and ideas I found.   The machine replicates the technique but not the sensitivity.   This applies to the industrial revolution. It will become more expensive and elite to own something made through Craftsmanship art. People are going back to older techniques. You know how to do it by hand, and even with paint, and who knows, maybe even with natural paint. The Aesthetics of the "Smooth": Today, we find beauty in things that offer no resistance and cause no pain—like smartphones, Jeff Koons’ sculptures, or hairless skin. It is the triumph of positivity, where everything strange or disturbing is eliminated. -----   Now I say this: Without sacrifice there is no lasting gratification, only momentary gratification. That's why this project feels good. That's why building an empire over centuries is rewarding. Building more than consuming. Life loses its meaning if everything is so easy and immediate. Value your talents, guys.

Only mention of Germans using sails seem to be during the Batavian Revolt, but they appear to be copying those in Roman ships (if not just replacing the sails in Roman ships that already had sails.)  

They should be licensed under that, yes.