Claudius Galenus (Galen) was born in Pergamum, Asia Minor in AD 129 or 130. The name Galenus means calm and peaceable, but Galen inherited from his mother part of her fiery temperament. His father was an architect and had a sound knowledge of mathematics, physics and natural sciences and for four years (until his death) he superintended the education of his son, ensuring that Galen was familiar with all of the current schools of thought. After his father's death Galen began his travels and further education. First he went to Smyrna, which had one of the finest medical schools of the day.

Here he began experiments on the role of the thoracic muscles and the diaphragm on respiration which, when developed later into a treatise on further experiments, laid down the modern knowledge of the action of respiratory muscles.

From Smyrna Galen went first to Corinth then to Athens. After returning home to Pergamum briefly he then went on to Alexandria, the highest seat of learning in the world at the time.

In AD 153 Galen went to Rome and undertook five years of post-graduate study.

His first professional appointment was in Pergamum as surgeon to the gladiators. This post was held for four years and he became expert in the surgery and particularly treatment of severe wounds. He introduced treatments intended to reduce infection and inflammation of wounds, indicating in a treatise that 'it is necessary to keep the wound continually moist, because if the dressing dries out, the ulcer becomes inflamed. I cured the most seriously injured by covering the wounds with a cloth wet with astringent wine, kept moist both day and night by a superimposed sponge'. He was also familiar with the suturing of severed tendons.

In AD 161 the Parthians revolted (unsuccessfully) but one result of this was that Galen moved to Rome (via Alexandria, Troy, Lemnos, Thessalonika and Greece) in AD 162. He remained for three years on this visit. He was well received by the learned laymen of the city but not so warmly welcomed by his fellow physicians. In Rome he acted as public demonstrator in anatomy and as medical practitioner. In the former role Galen often demonstrated the errors in the works of others, which did not increase his popularity! He was appointed physician to the Imperial family.

Galen spent AD 169 to 175 in Rome's seaport, Ostia. In AD 176 he joined Marcus Aurelius' army on an expedition to stamp out a revolt in the east.

In AD 178 Galen sold his possessions in Pergamum and returned permanently to Rome. Further works were published in AD 198. It is not known with certainty when or where Galen died.

Galen collected the safest teachings of others and added his own findings. His works are a fascinating combination of knowledge and ignorance, due in part to the lack of knowledge from human dissection. For example, he understood how muscles worked but not why; he was close to the discovery of blood circulation in that he judged health by the pulse but did not associate the pulse with the action of the heart; he used natural medicinal materials which he prepared himself to a high standard but had no idea of standardisation, although he was the first to prepare extracts by soaking his raw materials in wine and other solvents. Many of the extracts prepared following Galen's example are still in (limited) use today. In all he described 473 drugs of animal, vegetable or mineral origin as well as his own formulae. The collective name for such products is still 'galenicals'. Galen's belief in the beneficence of the Creator, which showed through in his writings, led to the acceptance of his ideas by the developing Christian Church to the exclusion of others. This lasted for some 1500 years and had the unfortunate effect that no medical investigations or original work worth mentioning was undertaken in Europe until the mid-1500s when Vesalius corrected some of Galen's errors (and was persecuted by some for doing so). The next major challenge was from Harvey, who corrected Galen's ideas of the movement of blood in the body between 1618 and 1628 and was also not well received by some for doing so.

This account is based in part on a leaflet on Claudius Galenus produced by Heartbeat Galen Lodge No 515, Australia.