Pho is younger than many assume. It is absent from a 1907 account of Vietnamese cuisine and emerged in the early 20th century around Nam Dinh, as French demand for beef left cheap bones and scraps that Chinese laborers and Vietnamese cooks transformed into a new noodle soup.

This episode weighs the French and Cantonese theories behind the name, explains the carrying-pole vendors who sold pho at dawn and dusk, and shows how beef shortages created chicken pho. We then follow the 1954 partition that split pho into northern and southern styles, the meatless pilotless pho of the subsidy period, underground vendors, and the diaspora that turned pho into a global icon.

• Why the French theory of feu is disputed and how a Cantonese street cry may have become pho
• How bamboo carrying poles let vendors haul a live fire and broth through the streets
• Why pho ga appeared around 1939 when beef was not sold on Mondays and Fridays
• The differences between restrained Hanoi-style pho and the herb-laden, sweeter southern style
• How restaurant names like Pho 75 and Pho 54 mark the years that uprooted families