Trade between Gaul and Great Britain is…

325 BCE

Trade between Gaul and Great Britain is by now routine; fishermen and others travel to Orkney, Norway or Shetland.

Pytheas, a Greek merchant, geographer and explorer from the Greek colony Massilia, journeys westward beyond the Mediterranean about 325 with a twenty-five-man crew.

He is not the first Mediterranean mariner to reach the British Isles.

The Massaliote Periplus is a more extensive fragment preserved in paraphrase in the Ora Maritima, a poem of the fourth century CE written by the Roman, Avienus.

This periplus of a ship from Marseilles on which the poem relies is uncertain in date, but is believed to be possibly from the sixth century BCE, not long after the founding of the city.

It primarily describes the coasts of southern Spain and Portugal, but makes brief mention of a visit to "the sacred isle" (Ireland, Ierne) located across from Albion (an early name for Britain).

The start of Pytheas's voyage is unknown.

The Carthaginians had closed the Strait of Gibraltar to all ships from other nations.

Some historians therefore believe that he traveled overland to the mouth of the Loire or the Garonne.

Others believe that, to avoid the Carthaginian blockade, he may have stuck close to land and sailed only at night.

It is also possible he took advantage of a temporary lapse in the blockade, known to have taken place around the time he traveled.

Carthage and Rome had come to terms over the Sicilian Wars in 348 BCE with a treaty defining their mutual interests.

Rome could use Sicilian markets, Carthage could buy and sell goods at Rome, and slaves taken by Carthage from allies of Rome were to be set free.

Rome was to stay out of the western Mediterranean, but these terms did not apply to Massalia, which had its own treaty.

Massaliotes during the last half of the fourth century BCE, the time of Pytheas, were presumably free to operate as they pleased; there is, at least, no evidence of conflict with Carthage in any of the sources that touch on the voyage.

A recent conjectural reconstruction of the journey Pytheas documented has him traveling from Marseille in succession to Bordeaux, Nantes, Land's End, Plymouth, the Isle of Man, Outer Hebrides, Orkney, Iceland, Great Britain's east coast, Kent, Helgoland, returning finally to Marseille.

Pytheas is the first person on record to describe the Midnight Sun, the aurora and polar ice, and the first to mention the name Britannia and Germanic tribes.

He may have been the first Mediterranean observer to distinguish between the Germanic and Celtic "barbarian" peoples of northern and western Europe.

Pytheas studies the production and processing of tin in Cornwall, important as the main source of the metal.

He finds during his circumnavigation of Great Britain that tides here rise very high.

He records the local name of the islands in Greek as Prettanike, which Diodorus would later render Pretannia.

This supports theories that the coastal inhabitants of Cornwall may have called themselves Pretani or Priteni, 'Painted' or 'Tattooed' people, a term Romans will later Latinize as Picti (Picts).

He is quoted as referring to the British Isles as the "Isles of the Pretani."