ASTOR, William Backhouse, American merchant and capitalist, eldest son of John Jacob Astor: b. New York, 19 Sept 1792; d. 24 Nov. 1875. He was trained in his father's business in the intervals of public school education; and the father is said to have remarked that “William would never make money, but would keep what he had.” At 16 he was sent to Heidelberg University, and at 18 went to Göttingen, where he was tutored by Bunsen, afterward the great chevalier. Returning to New York in 1815, he was made a partner in his father's foreign shipping trade, especially cultivating the Chinese field.
The firm was John Jacob Astor & Son till 1827, when it dissolved and both partners gave up the China trade to form the American Fur Company, of which William was president, but John Jacob the head manager till he withdrew from active business life a few years later. He was shortly followed into retirement by his son. By 1848 he had amassed a fortune of his own; besides receiving a legacy of half a million from his uncle Henry, and a gift of the Astor House from his father; the latter on his death in that year leaving him sole legatee save for minor bequests, the property being estimated at $20,000,000 to $30,000,000. His life thenceforth was spent in conserving and developing this. He built nearly a thousand houses on his uptown lots, and was currently termed “the landlord of New York.”
He was also a heavy investor in other lines, notably coal and railroad stocks. He founded the Astor Library under his father's bequest, adding by gifts and bequests over $600,000 to his father's gift, giving much time to its administration from the completion of the building in 1853 on his plans. His wife was the daughter of Madison's second Secretary of War; his sons were John Jacob and William, and the estate was shared between them.
Encyclopedia Americana, 1920