John B. Blydenburgh was born around 1845 in Brooklyn, New York, to Benjamin and Mary Blydenburgh. His father was a merchant and farmer who owned $8,000 of real estate by 1870. He grew up and attended school in Brooklyn, and by 1870, he was working as a clerk in Smithtown, New York. By 1900, he was working as a merchant. He moved to Claverack, New York, in the early 1900s, and he died sometime after 1910.