I keep coming across references to human sacrifice & sacrifice associated with burials in the academic texts I read. Before I started taking notes I never really realized how many different cultures do it, and now I'm trying to figure out if I should try to integrate it into my worldbuilding. I've seen a couple of books pull it off...
- Sati (suttee?) was a historical Hindu practice, in which a widow sacrifices herself by sitting atop her deceased husband's funeral pyre.
- There's some evidence that the attendants of royalty in Bronze Age Mesopotamia were ritually sacrificed and entombed with kings and queens.
- There is a ton of controversy surrounding child sacrifice in the Punic world. My best guest is that it happened, but it was rare.
- Stateless societies sometimes sacrifice surplus food, burning it ceremonially in times of plenty.
- Deceased Scythians were often buried in their kurgans alongside their horses, who were killed, i.e. sacrificed.
According to Ibn Fadlan, a 10th century ambassador from Baghdad, Scandinavian settlers in Russia had a funerary practice that can best be summed up as the ritual murder of a rich guy's concubine-slave (apparently she volunteers — maybe her kids get something out of it?). He also saw them kill and cut up a dog, horses, chickens, but the sacrificial girl is definitely the eye-opening part. Evidently an old woman stabs her while men strangle her. Afterwards, her body is burned with the animals and the dead rich guy.
The Celtic festival of Beltane involves sacrifice. People at relatively recent festivals would pretend they're going to burn a guy to death. Apparently, archaeologists do think that the Celts practiced human sacrifice: the Lindow Man probably ate a "burnt bannock" before he was killed. It's a ritual food still used on Beltane, basically mistletoe pollen and unleavened bread. Then he was garroted, stabbed, and had his head bashed in before being tossed into a peat bog.
We don't really know how many people were actually sacrificed by the Aztecs, and may never know, but apparently there's an argument to be made that their habit of taking war captives for later sacrifice meant that their war-related casualties were actually lower than what was seen in other societies with comparable technology and rates of war.
The Romans only considered the way they interred Greeks and Gauls alive to be religious sacrifice / ritual murder. They buried unchaste Vestal Virgins alive and drowned hermaphrodites, but since it wasn't "sacrifice" they kept doing it after they banned human sacrifice around 97 BCE.
Note: There are a couple of affiliate links & codes scattered around, but these always come from links I was already recommending and usually I share them because they benefit you too (i.e. getting you extra time on trials).