The Ancient Greek physician Galen (5 letters) was a prominent figure in the development of medicine and medical science. He was born in 129 AD in Pergamon, Asia Minor, and is considered one of the most accomplished medical minds of antiquity. He wrote extensively on anatomy, physiology, pathology, pharmacology, and therapeutics, and his works were used as the basis for medical education for centuries. He also developed theories on the circulation of blood and the nervous system, and his influence on medical thought has been immense.