Bloodletting appears independently in ancient Egyptian, Mesopotamian and Greek sources with no single first documented instance; unlike cataract surgery (dated to Daviel, 1750) or vaccination (dated to Jenner, 1796), it has no founding event to anchor an origin year.
What would resolve this A dated papyrus, cuneiform tablet or other primary source establishing the earliest attested instance of deliberate therapeutic blood withdrawal, or a specialist historical consensus that no such instance can be recovered.
OpenMedical HistoryRoy Porter, The Greatest Benefit to Mankind: A Medical History of Humanity