Isaac Alfred Tobias was the first child born to Tobias Tobias and Rebecca Levy Tobias after they moved from England to New York. His father was a merchant specializing in the importation and sale of wine and liquor.

In 1847 he married Hermione Hendricks, daughter of Harmon and Frances Isaacs Hendricks. In doing so, Isaac was following in the footsteps of three siblings who had married Hermione’s siblings: Fanny Tobias had married Uriah Hendricks in 1826, Harriet Tobias had married Henry Hendricks in 1829 and Henry Tobias had married Roselane Hendricks in 1839. Isaac and Hermione would spend their lives in New York, where they raised their five children.

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