Born in Bridge Point, New Jersey, Bergen attended Harlingen School and Edge Hill Classical School and was graduated from Princeton College, where he studied law, in 1863. He was licensed by the supreme court of New Jersey in 1866 as an attorney and commenced practice in Camden, New Jersey.
Congress
Bergen was elected as a Republican to the 51st and 52nd Congresses, holding office from March 4, 1889, to March 3, 1893. He was an unsuccessful candidate for renomination in 1892, after which he resumed the practice of law.