Other way around - divide et impera means that Rome attempted to divide their enemies so they could conquer them one at a time (or rule them peaceably while they were focused on hating each other, since ‘impera’ means ‘rule’).
The Roman Kingdom certainly didn’t divide itself to conquer its enemies. The Crisis of the Third Century included some of the Empire dividing itself, but certainly not conquering anyone - Rome lost territory during the Crisis. The Dominate likewise was a period in which land was largely lost, not gained.
Other way around - divide et impera means that Rome attempted to divide their enemies so they could conquer them one at a time (or rule them peaceably while they were focused on hating each other, since ‘impera’ means ‘rule’).
Hum… People do have a really strong bias toward looking at only the republic era and the first few decades of the empire.
… what?
The Roman Kingdom certainly didn’t divide itself to conquer its enemies. The Crisis of the Third Century included some of the Empire dividing itself, but certainly not conquering anyone - Rome lost territory during the Crisis. The Dominate likewise was a period in which land was largely lost, not gained.
Where you got that it was to conquer its enemies? (Edit: Oh, reading my post again I see where you got that idea.)
It was always dividing itself and conquering itself again. Unless you count parts of it as enemies (what would be reasonable).