He received his early education at the common schools of his native town.
The family in 1842 moved to New York City, and he obtained a situation in the law office of Willett & Greig at one dollar per week. He was called to the New York bar in 1849, at the same time becoming office manager for the firm. He had already impressed people with his business aptitude, and when, on the death of Greig, he opened an office for himself, he attracted many of the old clientele. A characteristic manifested early in his career was a reluctance to resort to litigation if any other method of achieving the settlement of a claim appeared possible. Consummate tact combined with an almost uncanny knowledge of human nature made him an adept at contriving compromises of dangerous disputes. His first important retainer was on behalf of the claimants under the Mexican Treaty following the War of 1846-47. He soon had more business than he could individually attend to, and in 1852 the firm of Bowdoin, Larocque & Barlow was formed, changed in 1881, when Judge Choate entered the firm to Shipman, Barlow, Larocque & Choate.
Barlow's name became increasingly associated with heavy corporation work involving large financial interests. He made no pretence to being an advocate, and hardly ever appeared in court. His great successes were achieved at the consultation board, where his unerring judgment and a lightning-like capacity of appreciating the crucial point of a problem made him a commanding figure. His skill as a mediator was well exemplified in the Vanderbilt-Aspinwall case. Commodore Vanderbilt and William Aspinwall had become bitter enemies over their conflicting Nicaragua and Panama schemes, and were not on speaking terms. Barlow's interest in the dispute was only as representative of a small number of Pacific Mail shares, the pecuniary value being insignificant, but he determined to intervene. He asked the two enemies to dinner at his house, neither having knowledge that the other would be present, and in a tête-à-tête discussion, effected a reconciliation.
Another instance of his appearance as deus ex machina was in connection with the Garrison contract. During the Franco-German War Commodore Garrison and associates held a contract with Gambetta to supply the French Government with arms, the amount involved being $1, 000, 000. When Gambetta was driven from office his successor, Thiers, repudiated the contract as exorbitant, thus leaving a ship-load of arms in the hands of the American contractors. Bitter dissensions among the latter threatened disastrous litigation, when Barlow, on behalf of a minor member of the syndicate, intervened, arranged a conference, reconciled the malcontents, induced them to entrust their whole interests to him, and within three months had adjusted the matter with the French authorities, and procured payment of the whole amount involved.
The only spectacular event in his career arose in the course of the protracted struggle for control of the Erie Railway, 1872-89. There had been great dissatisfaction with the management of the railway by Jay Gould and James Fisk, Jr. , which came to a head after the death of the latter in January 1872. Barlow was retained on behalf of the English Shareholders' Association. Under his advice and with his active participation, the Grand Opera House in New York - headquarters of the company - was forcibly taken possession of, on March 11, 1872, the personnel of the board of directors changed, and Gould ousted, in contempt of an injunction decree obtained by Gould from the court. Barlow also commenced suit against Gould for $9, 726, 541. 26 alleged to have been fraudulently appropriated from the company's funds. The action was compromised, Gould paying $9, 000, 000 in full settlement, December 18, 1872. On the reconstitution of the Erie Company, Barlow remained the dominant figure in the company's affairs till May 1875.
He died suddenly on July 10, 1889, at his country estate, "Elsinore, " Glen Cove.
Barlow took an active interest in politics. An ardent Democrat, he opposed Tilden and Van Buren and the Free-Soil party in 1848. In 1856 he strongly supported Buchanan, and was the decisive figure in the nomination of Breckinridge as vice-president. Although he opposed the election of Lincoln, he supported the administration whole-heartedly during the war. He was an intimate friend of Gen. McClellan, and assisted his candidature for the presidency in 1864.
Barlow was also a member of the high-class Manhattan and Union clubs, the former of which he helped found.
In early life he was handsome and fond of dress, but later on became very stout. It is related that he attempted to reduce himself by horseback riding, but after a short trial it was discovered that his horse had lost fifty pounds and he had gained five. Thereafter he allowed nature to take its course. He was very hospitable, a bon vivant, and "almost rivalled Sam Ward in his tastes as an epicure. "
An enthusiastic bibliophile and art connoisseur, he assembled a fine library specializing in works on the early history of America. His collection was one of the most valuable in America, since it consisted mainly of original editions and authorities. His collection of paintings and objets d'art was equally extensive and more eclectic. The gem of the collection was Van Dyck's "Children of Charles I, " purchased by C. P. Huntington for $8, 500.
Above all he loved dogs, and for years was a successful exhibitor at the Madison Square Garden dog shows. An expert whist player, he wrote the article on "Whist" in Appleton's Encyclopædia. In conjunction with Henry Harrisse he edited Notes on Columbus (privately printed 1865), and at his own cost printed for private distribution a number of scarce works on American subjects, dealing chiefly with Columbus.
Barlow married Alice Cornell Townsend, with whom he had one son, Peter Townsend Barlow.