Another theory that Vietnamese cuisine experts agree on is that the birthplace of pho is northern Vietnam, near Hanoi. Given the theory that pho is a Vietnamese adaptation of the French pot au feu, it is not surprising to think that pho originated from the north.
Hanoi has always been the center of political power in colonial Vietnam,
with only a few short interruptions. The city has always been the seat
of Vietnamese kings and emperors since 1010, except during the rule of
the Nguyen dynasty, when the capital was moved to Hue. When the French
conquered Vietnam and established the colony they called the French
Indochina, they made Hanoi their capital city.
The French brought pot au feu to Vietnam and introduced the idea of slaughtering cows for food to the Vietnamese of the north. The northern regions of Vietnam are not as rich as those in the south, and food scarcity is not a stranger to a northern Vietnamese household. The northern Vietnamese get their food where they can find it, and they learned to take the beef parts and bones that their French conquerors did not want for their table. It is widely believed that this is how pho of the north, called pho bac, came to be.
Pho bac has an intense and delicate flavor that is entirely different from pho nam, which is pho of the south. The focus of pho bac is on the taste of its clear and simple broth. The star anise and other spices commonly used in pho serve as subtle undertones of flavor rather than complex layers. The main ingredients in pho bac are the rice noodles and the thinly sliced rare beef cooked quickly in the hot broth. You would not find a bowl of pho bac topped with the popular herbs and garnishing found in pho nam or in pho outside of Vietnam.
Even today, northern Vietnamese and pho purists consider pho bac the true pho. It is not uncommon to find a person from northern Vietnam or a pho purist to turn away from lavish preparations of pho nam or from pho that is not made from beef stock. Some of them find such preparations shocking and even disgusting.
Note's Vietnamese Pho of the North: I want to clarify here that, all this is a generalization. Of course Viet people had beef on their menus. But the fact is, beef is an expensive food ingredient for many Viet people. Even in the early 1970, our family, which I would describe as “middle-class” in Vietnam at the time, had beef maybe once per week on the average in our meals, not more. In general, for the very well-to-dos and during festivals and celebrations, slaughtering cows or other animals is part of the tradition. It should also be noted that, we use both water buffalos and cows to till the land, with water buffalos being the more dominant in this role and cows also for food. As a result, it is less likely to find water buffalo meat as an ingredient in everyday Vietnamese cuisine.