Mary Walton married Lewis Morris, signer of the Declaration of Independence, in 1749. She came from a well-known family of merchants in New York City. The family business was started by her grandfather, William Walton, and continued after his death by her father, Jacob Walton, and his brother William. Her mother was Maria Beekman, daughter of Dr. Gerardus Beekman. According to James Grant Wilson's History of New York City, the "most historic family of merchants was that of Walton, whose wealth was cited in parliament to show the wealth of the Province."
Mary was a very capable, well-trained, and thrifty housewife in spite of her wealth and social position. She was an active partner with her husband in rural life when he inherited the family manorial estate of Morrisania. Mary and Lewis were parents of ten children: Lewis, Jacob, William, James Staats, Richard V., Catharine, Mary, Sarah, and Helena. Their three oldest sons served with honor and great credit in the Revolutionary Army.
Even though the Walton's large property was close to New York City and would probably suffer from war, Lewis encouraged leaders in New York to resist British efforts to encroach on the rights of the people. When he signed the Declaration of Independence, he became a marked man. His family fled to safety, but his estate was nearly destroyed with his house ruined, his farm wasted, his cattle driven away and his forest of a thousand acres destroyed.
Lewis retired from Congress in 1777 and was succeeded by his brother, Gouverneur Morris. Lewis, however, continued to be active in public affairs as a member of the state legislature and in the field with the state militia. After the Revolutionary War ended and the British left America, the Morris family returned to Morrisania and "cheerfully" worked to return the nearly ruined estate to resemble a home.
Mary Walton Morris and Lewis Morris were both laid to rest in the family vault located at St. Ann's Church (Episcopal), St. Ann's Avenue and 40th Street, Bronx, New York.
Facts and quotes are from Wives of the Signers: The women behind the Declaration of Independence, pp. 126-132.