This motto was made a part of the Territorial Seal of Oklahoma in 1893, then later became a part of the Great Seal of Oklahoma with the adoption of the state constitution in 1907.
Grand Seal of the Territory of Oklahoma
The Great Seal of the State of Oklahoma
Labor Omnia Vincit (close up)
The Latin phrase "Labor Omnia Vincit" was derived from a writing by Roman poet Virgil: Georgics (I, 145), "Labor omnia vicit improbus" (Never-ending work conquered all things).
vicit is the past tense "conquered" of vincit "conquers"
The Georgics, written in 29 BC, is the second major work by the Virgil. The poems were written in support of a campaign by Augustus Caesar to encourage more Romans to take up farming.