Algorithm for the unification of France?

The unification of France into a single state began during the Frankish Empire, when, according to the Treaty of Verdun of 843, Charles the Second the Bald seized Neustria, the northwestern part of Austrasia, Vasconia, Septimia and the Spanish Mark, forming the West Frankish kingdom. By Philip the Second Augustus, the possessions controlled by the king and his vassals were expanded as a result of the war with the Plantagenets. In 1202, John Landless was deprived of all possessions in France. Disagreeing with this, the English prince convened an anti-French coalition, which in 1214 was utterly defeated by Philip at the Battle of Bouvin. France was left with Normandy, Anjou, Touraine, Maine and Poitou. In 1312, after the weakening of the Holy Roman Empire, Lyon was annexed to the territory of the French kingdom. In the same century, the Duchy of Dauphine was acquired. In the 15th century, as a result of the dynastic union of Charles the Eighth with Anne of Breton, Brittany joined the French possessions, and already during the period of absolutism, the borders of the state acquired their modern outlines. Corsica became part of the state in the 18th century. It should be noted that the modern borders of France were established after the Second World War, when Alsace and Lorraine finally became part of it.