What is the origin of the idiom "divide and conquer" and when to use it?

The origin of the idiom "divide and conquer" can be traced back to ancient times. The concept has been used by various military and political strategists throughout history. The phrase itself is commonly attributed to the Roman general Julius Caesar, who reportedly said, "Divide et impera" (Latin for "divide and rule"). This phrase is used in various contexts and occasions where strategies of fragmentation and control are employed.