"Barbaren" means "barbarians" in German[...] There is no [character named] "Barbara" in the libretto.
First in its original form, from G.W. Pabst's 1931 film Die Dreigroschenoper:
And by Gil Evans, one of the greatest things ever in jazz:
By Tethered Moon, a trio with pianist Masabumi Kikuchi, Gary Peacock, and Paul Motian:
Those are the big three in my book, but there are couple more after the break: