[umgud]

So Cain slew Able (world’s 1st born, brothers), then went out into the boonies and hooked up some gal. Who was she? Who was she and Cain’s offspring? Neandethals? Some other lineage/

[PAR35]

My pet theory is that the Neanderthals don’t show up until Genesis 6. “ There were giants in the earth in those days; and also after that, when the sons of God came in unto the daughters of men, and they bare children to them, the same became mighty men which were of old, men of renown.”

[Harmless Teddy Bear]

So Cain slew Able (world’s 1st born, brothers), then went out into the boonies and hooked up some gal

Yeah. No.

. Who was she?

His younger sister.

Who was she and Cain’s offspring?

People who built cities.

Neandethals?

Haven't seen any Neanderthal cities yet but since they were just humans could be.