Michelangelo (1475-1564) belongs in the Renaissance, not the Dark Ages, a name given to the period roughly between the deterioration of the Western Roman Empire and the later Middle Ages.
And one might add that Medieval times and the period “Dark Ages” is most often applied to are distinct. The time between the collapse of the Western Roman Empire around 450 AD and the rise of Charlemagne as Holy Roman Emperor was indeed dark. Classical knowledge was forgotten, Christianity itself was largely displaced by paganism everywhere but Ireland and a small territory around Rome itself, and few written records were made of what went on, leaving later scholars in the “dark”. Christian missionary and by conquest reconversion of the west and the prolific writing and scholarship of the monasteries switched the lights back on.