In 1827, Alfred was a clerk for Eli Hart & Co., a flour merchant in New York City. In the 1840s, he had a seat on the New York Stock Exchange. On April 16, 1849, Alfred married Margaret Wynkoop Kittle, daughter of Andrew Nicholas and Eliza (Gosman) Kittle. Later that year, he sailed to San Francisco with a cargo of merchandise to join in the Gold Rush (the journey took 180 days). Shortly after arriving in San Francisco, he and Henry A. Harrison founded DeWitt & Harrison – Importers, General Commission, Merchants, and Wholesale Dealers with warehouses at 189 and 191 Sansome Street. Their company organized a line of express clipper ships that sailed regularly from New York to San Francisco, largely transporting goods, including cement, to California. During his time in San Francisco, he became an amateur painter, and some of his works are in the collections of the Society of California Pioneers.

From his earlier New York days, Alfred DeWitt was close friends with Alexander Joy Cartwright, the "Father of Modern Base Ball" (Cartwright's son DeWitt was named after Alfred). Along with Cartwright, Alfred and his brothers Peter, Theodore, and Henry were involved with the Knickerbocker Base Ball Club of New York City, one of America's first baseball clubs (formally organized in 1845). John Thorn proposes that Alfred DeWitt played in the first recorded baseball game in San Francisco at Portsmouth Square on February 4, 1851.

In 1854, Alfred opened a branch of DeWitt & Harrison in New York. Alfred's brother-in-law, Nicolas Gosman Kittle, joined the firm in San Francisco, and they changed their name to DeWitt, Kittle & Co. In 1866, the San Francisco branch moved to 202 California Street. During these years, Alfred often traveled back and forth between San Francisco and New York, often with his wife Margaret. When Alfred retired in 1870, the firm changed to Kittle & Co. and he and Margaret returned full time back East in New Jersey. After Margaret died, he moved to his home Staatsburg, New York – not far from the source of the cement he'd previously transported to California during the Gold Rush.
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Sources:

Malcolm J. Rohrbough (1998). Days of Gold: The California Gold Rush and the American Nation. Los Angeles, California. University of California Press.

The Society of California Pioneers (2007). "From Empire State to Golden Gate: Alexander Joy Cartwright and the Pacific Coast League."

Frank Soule, John Gihon, & James Nisbet (1855). The Annals of San Francisco. North Charleston, South Carolina. Createspace.

John Thorn (2013). "The Knickerbockers: San Francisco's First Baseball Team." Our Game blog.

Thanks to Ken DeWitt Thomas (47617690) for providing the biographical information above. • [email protected]
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Rhinebeck Gazette, Rhinebeck, Dutchess County, NY 14 Oct 1899 - Alfred De Witt who was once the City Treasurer of Elizabeth, NJ died Wednesday in Staatsburgh at his summer residence. Member of the Holland Society of NY; one of last California pioneers.
Thanks to Beverly Kane (#46485975) for this information.
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