The emergence of undersea and hyperbaric medicine is closely linked to the history of Diving itself, although it would not be until Robert Boyles' experiments in 1670 that the first trace of the study and causation of DCI would begin.

Early breath-hold divers, dating back more than 5000 years, were confined to work in waters less than 30metres (100feet) deep, these 'first' divers performed tasks such as harvesting food, coral, sponges and pearl as well as the odd ship salvage, a task which still captivates the attention and imagination of most modern age divers. One of the earliest recorded exploits of divers is that of the Greek Scyllis, as told by the Greek historian Herodotus:

Whilst engaged in a sea battle, scyllis was taken prisoner aboard the Persian King Xerxes's ship. Learning of an attack on the Greek flotilla, he seized a knife and jumped overboard. The Persians could not find him and presumed he had drowned. Scyllis remained hidden and later surfaced under cover of darkness and made his way amongst Xerxes' ships, cutting each ship loose from its moorings; he accomplished all of this by breathing through a hollow read. Then he swam nine miles to rejoin his Greek comrades.

Robert Boyle and the history of Hyperbaric Medicine »