Carthaginian Peace is the imposition of a very brutal 'peace' by completely crushing the enemy. It derives from the peace imposed on Carthage by Rome. After the Second Punic War, Carthage lost all its colonies, was forced to demilitarize, pay a constant tribute to Rome and could not enter war without Rome's permission. At the end of the Third Punic War the Romans systematically burned Carthage to the ground and enslaved its population.
The term refers to the outcome of a series of wars between Rome and the Phoenician city of Carthage, known as the Punic Wars. The two empires fought three separate wars against each other, beginning in 264 BC and ending in 146 BC.
At the end of the Third Punic War, the Romans laid siege to Carthage. When they took the city, they killed most of the inhabitants, sold the rest into slavery, and destroyed the entire city. Some modern accounts say they plowed over the city and sowed the ground with salt, but this is not supported by ancient sources.
By extension, the term "Carthaginian Peace" can refer to any brutal peace treaty demanding total subjugation of the defeated side.
Modern use of the term is often extended to any peace settlement in which the peace terms are overly harsh and designed to perpetuate the inferiority of the loser. Thus many (the economist John Maynard Keynes among them) deemed the post-WWI Treaty of Versailles to be a "Carthaginian Peace." The post-WWII Morgenthau Plan might be described as a Carthaginian Peace, as it advocated the 'pastoralization' (de-industrialization) of Germany following her 1945 defeat in World War II. The Morgenthau Plan was dropped in favor of the Marshall Plan (1948–1952),
General Lucius D. Clay, deputy to general Dwight D. Eisenhower who in 1945 was military governor of the U.S. occupation Zone in Germany, and who would go on to replace Eisenhower as governor and as commander in chief, U.S. Forces in Europe, would later remark regarding the occupation directive guiding his and General Eisenhower's actions in occupied Germany: "there was no doubt that JCS 1067 contemplated the Carthaginian peace which dominated our operations in Germany during the early months of occupation. This is while the US was following the Morgenthau Plan."