Born in Antwerp, Rysbrack (who usually signed himself Michael, rather than John Michael) came to London in 1720. By the time of his retirement in 1764, he had risen to the position of premiere portrait sculptor in England. Among his patrons were the royal, noble and notable men of his time.

He worked from his own sketches or clay models; he is known to have carried a ball or "plug" of clay in his pocket, in order to make three-dimensional on-site sketches with his fingers. His busts and statues are in the baroque style; his representations are heroic; his works are highly finished, with polished surfaces. Rysbrack was a gregarious man, member of several clubs, a founding Member of the Royal Academy, and an Associate of the London Foundling Hospital.