Yes, as I mentioned earlier, even our prehuman ancestors knew about the existence of gravity. Most sentient animals know that things fall down.No, even animals knew about gravity before Newton. That's the reason they don't jump off cliffs.
(To be fair, Indian astronomers in antiquity have gone a little further than that in describing it. But they did not describe it in the way Newton did, and to the best of my knowledge, nobody quantified it before Newton.)