De oppresso liber

De oppresso liber is the motto of the United States Army Special Forces.

In the United States Army Special Forces, the motto is traditionally believed to mean "to free from oppression" or "to liberate the oppressed" in English.

A correct translation of the phrase de oppresso liber would be "from (being) an oppressed man, (to being) a free one".

The preposition de here means "from" in the sense of a change from one status to another, not intending separation from the oppressed, but moving from a source in the oppressed. Compare Ovid Fasti 5, 616: inque deum de bove versus erat, "he had been changed from an ox into a god", or Juvenal 7, 197: fies de rhetore consul, "from an orator you will become a consul". Oppresso is the past participle of opprimere ("to oppress") in the ablative case as governed by de, meaning "an oppressed person". The adjective Liber is in the nominative case, "a free person".

The motto resembles a quote from St. Augustine:corripiendi sunt inquieti, [...] oppressi liberandi, "the turbulent have to be corrected, [...] the oppressed to be liberated". See also Isaiah 1:17: subvenite oppresso, "relieve the oppressed".

The phrase stems from the exploits of World War II Office of Strategic Services Jedburgh/Sussex Teams operating behind the lines in France. Colonel Aaron Bank, father of United States Army Special Forces, and his teams enabled the French Resistance to grow and oppose the occupying German Army. The unconventional warfare tactics of Colonel Bank differed from the conventional warfare tactics of the rest of the United States Army in that they included clandestine support for one side of an existing conflict and that they were subversive to the Nazi forces in power.

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