Cannibalism has been documented again and again in archaeological contexts, as part of normative human behavior. Here’s a recent report (I’ve not looked yet at the original) from the German Neolithic:
Archaeologists have found evidence of mass cannibalism at a 7,000-year-old human burial site in south-west Germany, the journal Antiquity reports.
The authors say their findings provide rare evidence of cannibalism in Europe’s early Neolithic period.
Up to 500 human remains unearthed near the village of Herxheim may have been cannibalised.