Barnett–Hanna Trading Post — Samuel Hanna's store (later S. Hanna & Co.)

1819 – by succession

Founded: 1819 — Samuel Hanna, aged 22, took his trading venture to Fort Wayne in 1819, the year the garrison withdrew, and built his log store at what became the northwest corner of Barr and Columbia streets (History Center, Castaldi). The Barr-and-Columbia intersection marker independently inscribes "North West — Barnett-Hanna Trading Post 1819." A near-contemporary memoir quoted in Slocum & Robertson (1905) agrees: Hanna arrived in 1819 and "immediately entered upon mercantile pursuits in a small way, at what is now the north-west corner of Columbia and Barr streets," his first storehouse "a rude log cabin, erected mainly with his own hands."

Founders: Samuel Hanna (1797–1866). The "Barnett" in the marker name is James Barnett, Hanna's early Fort Wayne partner — the partnership is recorded as a trading pairing (Lasselle's trader list, Indiana Magazine of History, written c.1859: "Barnet and Hanna traded at the same place [Fort Wayne]"), and Hanna and Barnett later built the town's first gristmill together. The exact years of the Barnett partnership at the post are not established on the sources in hand — Lasselle dates their joint trading 1824–1828, which sits awkwardly against the marker's 1819 post date; no partnership start year is stated until the Hanna ledgers settle it. Hanna & Company business records do survive from the 1820s: an Indiana Magazine of History study of Hanna clerk Lathrop M. Taylor cites "Hanna and Company Ledger A, 1827" and a "Hanna and Company Invoice Book, 1827–1828" — the firm's own books, quoted from the originals.

What it did: Indian trade and general merchandising at annuity time — trade goods brought up the St. Marys or overland, exchanged with the Miami and other peoples receiving government annuity payments at the Fort Wayne agency; Hanna was soon appointed agent of the American Fur Company (Slocum memoir, quoted 1905).

Course: The log cabin was superseded by a frame building, then by "a substantial brick block of business houses" on the same corner (Slocum memoir). Hanna expanded the mercantile operation beyond Fort Wayne — to Lafayette, Wabash and South Bend (the South Bend post run by his clerk, then partner, Lathrop M. Taylor from 1827; the firm there became Hanna and Taylor) — and became an extensive Wabash Valley landowner. Hanna himself went on to promote the Wabash & Erie Canal, the plank roads and the railroad, but those are promotions, not this firm.

Fate: Closed by succession, no single closure date in hand — thin at the end. Hanna died 11 June 1866 (History Center). The business continued at the old corner under his sons as S. Hanna & Sons, general merchandise, Columbia and Barr — Slocum (1905) names eldest son Jesse Bayless Hanna and son Amos Thomas Hanna as members of that firm and notes the old building was "still in existence" in 1905. When S. Hanna & Sons itself ceased is not established on the sources in hand; ACPL / city-directory work (1858 onward) is the route to a closure date.

Sources:

1. History Center Notes & Queries, Tom Castaldi, "Samuel Hanna: The Founder of Fort Wayne" — http://historycenterfw.blogspot.com/2013/07/samuel-hanna-founder-of-fort-wayne.html
2. HMdb, "This Barr And Columbia Street Intersection" marker (inscription transcribed) — https://www.hmdb.org/m.asp?m=197325
3. Slocum & Robertson, History of the Maumee River Basin (1905), Part 6 (G. W. Wood memoir of Hanna, transcribed) — https://ldsgenealogy.com/IN/books/History-of-the-Maumee-River-basin-Allen-County-Indiana-part-6.htm
4. Lasselle, "The Old Indian Traders of Indiana," Indiana Magazine of History (1906, from an c.1859 account) — https://scholarworks.iu.edu/journals/index.php/imh/article/download/5550/4823/17002
5. Anson, "The Early Years of Lathrop M. Taylor, The Fur Trader," Indiana Magazine of History (Hanna and Company Ledger A, 1827; Invoice Book 1827–1828) — https://scholarworks.iu.edu/journals/index.php/imh/article/download/7735/9184/21426