“Go West, young man, go West and grow up with the country.” The advice is often credited to the newspaper editor Horace Greeley. Nobody has proven who first used the phrase in print.
One story names John B. L. Soule and an 1851 editorial in the Terre Haute Express. The phrase does not appear in any 1851 edition of that paper, and the Soule story goes back to a satirical account from 1890. Greeley himself denied giving the advice.