Natural borders of France

According to University of California, Berkeley, historian Peter Sahlins, "as a model of French identity, it formed part of a constitutive myth of the state.

The Prussian Anacharsis Cloots published that year the Wishes of a Gallophile (French: Voeux d'un gallophile) and pronounced himself in favor of the annexation by France of the left bank of the Rhine, "natural boundary of the Gauls" (French: borne naturelle des Gaules).

After the victory of Valmy on September 20, 1792, the National Convention urged the soldiers to go after the Prussian armies of the other bank of the Rhine.

For General Adam Philippe, Comte de Custine, commander of the Army of the Rhine, "if the Rhine is not the limit of the Republic, it will perish" (Si le Rhin n'est pas la limite de la République, elle périra).

"[1] The Army of the Alps invaded Savoy, part of the Kingdom of Sardinia allied with Austria, and took it with very little resistance between the September 21 and 22, 1792.

The victories of Napoleon Bonaparte in Italy forced Austria to sign the treaty of Campo Formio on October 27, 1797.

The French government reorganised the newly enlarged left bank of the Rhine and created four new departments: Mont-Tonnerre, Rhin-et-Moselle, Roer and Sarre.

The convention finally voted for annexation of Belgium on October 1, 1795, creating the nine Belgian départements: Dyle, Deux-Nèthes, Escaut, Forêts, Jemmape, Lys, Ourte, Meuse-Inférieure, and Sambre-et-Meuse.

Under the Consulate and the First French Empire, Napoleon expanded France to its theoretical natural borders through his conquests, mainly with the goal of controlling the coasts.