en_tn_condensed/jdg/02/10.md

All that generation was also gathered to their fathers

This means that as the people of that generation died, their souls went to the same place as their ancestors who died before them.

grew up

"grew older" or "became older"

who did not know Yahweh

Here "did not know" means they had not experienced Yahweh or his power the way the previous generation had.