Did you know that the expression "Mumbo Jumbo" dates back to Africa, where, whilst some tribes near by though Mumbo Jumbo was a god, However, there was a tribe or group of tribes or whatever, where polygammy was the norm. In this tribe, or group of tribes, or whatever, in order to keep their wives in line, the women believed in an idol called "Mumbo Jumbo". Mumbo Jumbo would appear at night and start screaming non-sense (which is where the expression comes from). What they didn't know was was that Mumbo Jumbo was actually the woman's husband in disguise, who would bash his rebellious wife with a stick.
So the origins of an expression about talking nonsense is actually derived from African wife bashing