City Readers Digital Historic Collections at the New York Society Library

James Beekman Jr., a merchant, was born in 1758. He lived with his family at Mount Pleasant, an estate on the East River, beginning in 1764 (Harrison 14). He entered Princeton in 1769 with his two older brothers, William and Abraham Keteltas, and attended the grammar school (Harrison 14). He attended Princeton intermittently between 1769 and 1775, when the American Revolution broke out and in September 1776 he moved with his family to Kingston, New York ("New York"; Harrison 14). He assisted his father and his uncles in their business during the war, and in 1787 he became a full partner in the family's firm, James Beekman & Sons (Harrison 14-15). He was a lieutenant in the New York County militia in October 1786, promoted to captain in 1788, and in March 1796 was the first major of the Fifth Regiment (Harrison 15-16).

Beekman's parents were merchant James Beekman and Jane Keteltas Beekman. His uncles were New York Society Library members William Beekman and Gerard W. Beekman Sr., and his cousin was Catherine Cox. He was the brother of New York Society Library members Abraham K. Beekman, Gerard W. Beekman, John K. Beekman, and William Beekman. He was married to Lydia Watkins Dew ("New York").

In 1783, during George Washington's triumphal reentry into New York City on Evacuation Day, Beekman rode in the celebratory parade (Harrison 15). After the death of his older brother William, he inherited Mount Pleasant ("New York").

Beekman died on April 8, 1837 (Harrison 16).