E pluribus unum (Latin for “Out of many, one”, alternatively translated as “One out of many” or “One from many”) is a phrase on the Seal of the United States, along with Annuit cœptis (Latin for “He approves (has approved) of the undertaking”) and Novus ordo seclorum, (Latin for “New Order of the Ages”) and adopted by an Act of Congress in 1782. Never codified by law, E pluribus unum was considered a de facto motto of the United States until 1956 when the United States Congress passed an act (H. J. Resolution 396), adopting “In God We Trust” as the official motto.
The phrase is similar to a Latin translation of a variation of Heraclitus‘s 10th fragment, “The one is made up of all things, and all things issue from the one.” A variant of the phrase was used in Moretum, a poem attributed to Virgil but with the actual author unknown, describing (on the surface at least) the making of moretum, a kind of herb and cheese spread related to modern pesto. In the poem text, color est e pluribus unus describes the blending of colors into one. St. Augustine used a variant of the phrase, ex pluribus unum, in his Confessions.
The traditionally understood meaning of the phrase was that out of many states (or colonies) emerge a single nation. However, in recent years its meaning has come to suggest that out of many peoples, races, religions, languages, and ancestries has emerged a single people and nation—illustrating the concept of the melting pot.