He participated in the battles of Saratoga and Monmouth, in Sullivan's expedition against the Native Americans in 1779, and in the Virginia and Yorktown campaigns, in which he served for a time on the staff of the Marquis de La Fayette.

[7] Along with Hamilton, he served in New York Militia Hearts of Oak (1st Battalion/5th Field Artillery Regiment).

Nicholas Fish's portrait can be seen at far right bottom row of John Trumbull's Surrender of Lord Cornwallis painting.

On two occasions, Fish ran unsuccessfully for United States Congress, losing to Samuel L. Mitchill in 1804 and Gurdon S. Mumford in 1806.

Fish ran in a special election for Lieutenant Governor in 1811 to fill the vacancy created by Broome's death, but lost to the then-mayor of New York City, DeWitt Clinton.

[3] Together, they were the parents of:[13][3] Fish died in 1833, and was buried in the churchyard of St. Mark's Church in-the-Bowery in New York City.