divide and conquer
To keep opponents from uniting so that each can be dealt with separately.
“He talked to each of them alone — classic divide and conquer.”
“Management offered a different deal to each department, and the union called it divide and conquer.”
“The strategy was divide and conquer from the first week: separate meetings, separate offers, and a carefully maintained impression that everyone else had already settled on terms better than the ones now being refused.”
Rome practised this long before anyone wrote it down as a maxim. After defeating the Latin League in 338 BC, Rome refused to negotiate with the league as a body. Each city got its own separate treaty on its own terms, some with citizenship, some without, none with the right to make agreements with each other. A dozen towns that could have combined against Rome were left facing it one at a time.
The Latin tag divide et impera — divide and rule — is not classical. It circulates in European political writing from the sixteenth and seventeenth centuries, applied retrospectively to Rome by people who had read Livy and admired the machinery.
English uses divide and conquer for anything from imperial policy to management technique: the deliberate work of keeping the other side fragmented, because a group that cannot agree on a position cannot press one.
Hannibal, Pyrrhus, and the strategy Rome used on everyone else.
- 01
Hannibal at the gates (idiom)
A threat so close and so serious that everything else stops mattering.
Hannibal in Italy, 218–203 BC.
- 02
a Pyrrhic victory (idiom)
A win that costs so much it feels almost like a defeat.
Pyrrhus beats Rome and loses anyway.
- 03
fortune favours the bold (idiom)
Luck tends to go to the person willing to take the risk.
Virgil, Aeneid X.
- 04
si vis pacem, para bellum (idiom)
If you want peace, prepare for war — the argument that strength is what prevents attack.
Vegetius on why armies train.
- 05
casus belli (idiom)
The event a side points to as its justification for going to war.
The paperwork of a just war.
- 06
semper fidelis (idiom)
Always faithful — a pledge of loyalty that does not expire.
The soldier's oath.
Last updated August 3, 2026