With a bit of further research I've also found this from http://www.hroarr.com/articles/article- ... gsword.php
"How far back does the federschwert actually go?
Of course we have little idea of what was used before we see the first illustrated manuals, but the first "federschwert" can be found in the "Gladiatoria Fechtbuch" Ms.Germ.Quart.16, as seen below. Interestingly enough this manuscript shows the federschwert in the context of harnischfechten, in armoured combat. This is is just about 45 years after the important, but not illustrated manuscript Hs.3227a, which currently is considered to be the earliest manuscript in the Liechtenauer tradition, dated to about 1390. Not without dispute, of course. "