Festival or Feast

Early in The Alexiad of Anna Comnena, there occurs a mention of a detachment of "Nemitzi", mercenaries whom the insurgent Alexius found partial to cooperation in regime change. Clearly these were Germans: Nemet or Nemeth is the word for "German" in a number of eastern European languages, but where does the name come from? I looked into Liddell and Scott, which offered no help on the point.

But any dictionary offers unexpected and interesting words, and Liddell and Scott offered

Νεμέσια (sc. ἱερά), τά,

A. festival of Nemesis, also held in honour of the dead, D.41.11 (v.l. -εια), “Ἑλληνικά” 3.154 (Rhamnus, iii B.C.).

This caught my eye, for Saki wrote a short story, "The Feast of Nemesis", the feast in this form being imagined by Clovis on the grounds that

There is no outlet for demonstrating your feelings towards people whom you simply loathe. That is really the crying need of our modern civilization.

I don't know that this is quite the crying need it may have been in the years before 1914. For that matter, very little in Saki's writings suggests any repression of such feelings towards those loathed, thought dull, or simply in the way as targets of opportunity.

Wikipedia, by the way, entry "Németh", says "literally Slavic for "he does not speak" (i.e., not a Slavic language)."