The Greek 'Far-West' in Gaul (500 BCE to 300 BCE)

This anachronic map of Phocaean and Gaulish settlements (not all of them existing or being occupied in the same time) illustrates an answer to the question There was a Greek-Phokian Colony at modern day Marseilles in the late Bronze/Early Iron Age. Did this Hellenized region influence the culture of Gaul? posted on the subreddit AskHistorians (the best place to ask, read or even answer serious and sourced question on History)