Divide et impera

Divide and rule (or divide and conquer, from Latin dīvide et īmpera) in politics and sociology is gaining and maintaining power by breaking up larger concentrations of power into pieces that individually have less power than the one implementing the strategy. The concept refers to a strategy that breaks up existing power structures, and especially prevents smaller power groups from linking up, causing rivalries and fomenting discord among the people.

Traiano Boccalini cites "divide et impera" in La bilancia politica as a common principle in politics. The use of this technique is meant to empower the sovereign to control subjects, populations, or factions of different interests, who collectively might be able to oppose his rule. Machiavelli identifies a similar application to military strategy, advising in Book VI of The Art of War (Dell'arte della guerra), that a Captain should endeavor with every art to divide the forces of the enemy, either by making him suspicious of his men in whom he trusted, or by giving him cause that he has to separate his forces, and, because of this, become weaker.

The maxim divide et impera has been attributed to Philip II of Macedon, and together with the maxim divide ut regnes was utilised by the Roman ruler Caesar and the French emperor Napoleon.

The strategy, but not the phrase, applies in many ancient cases: the example of Gabinius exists, parting the Jewish nation into five conventions, reported by Flavius Josephus in Book I, 169-170 of The Wars of the Jews (De bello Judaico).Strabo also reports in Geography, 8.7.3 that the Achaean League was gradually dissolved under the Roman possession of the whole of Macedonia, owing to them not dealing with the several states in the same way, but wishing to preserve some and to destroy others.

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