Isaac Newton formulated his three laws of motion in the late 1600s, specifically in his groundbreaking work "Philosophiæ Naturalis Principia Mathematica" published in 1687.

While it's accurate to say he "discovered" them, it's more accurate to say he formulated and systematized them. Earlier thinkers, like Galileo Galilei, had made important contributions to the understanding of motion, which Newton built upon and refined.