He was born on December 5, 1735 in Connecticut, United States. His father, Nathaniel, a native of Fairfield, Connecticut, settled in New London before 1730, became a sea-captain in the Irish trade, founded a mercantile house, and married Temperance Harris. The younger Nathaniel took over his father's business.
There is no information about his education.
Shaw Jr. took over the family business around 1763, when trade resumed after the Seven Years War. By the early 1760's he was an established merchant in the West Indian trade. Occasionally he transacted business in London and the Mediterranean, but commonly his brigs and sloops took lumber, cattle, or provisions to the West Indies and brought back sugar and molasses, either to be landed at his wharves and warehouses in New London or shipped direct to his correspondents, Peter Vandervoort of New York, Thomas and Isaac Wharton of Philadelphia, and George Erving or William Miller of Boston.
The British Acts of Parliament of the 1760's found Shaw unwaveringly on the colonial side. The Sugar Act made him an avowed enemy of those "cruizing Pyrates, " the revenue sloops, and as hard money became scarcer, he landed more and more cargoes without clearing at the custom house.
In 1769 Boston custom commissioners accused him of aiding in the destruction of the revenue sloop Liberty and of rescuing his own vessel with prohibited goods. His safe reply was an offer to maintain his innocence before any jury in the colonies. During these troubled years he participated as a leading figure in every form of organized colonial action against British restrictive measures. By December 1774 he was negotiating the purchase of powder for the general assembly; a year later he mournfully acknowledged the end of all trade. New duties awaited him, however.
The Council of Safety of Connecticut named him agent for the colony, with the task of fitting and supplying ships and caring for sick sailors, while the Continental Congress appointed him its agent in Connecticut to take charge of prize vessels and purchase necessaries for the fleet. He procured provisions, blankets, and tents for the Continental troops, cannon and powder, pilots to guide the French fleet into the Sound; he acted as commissary for the exchange of naval prisoners; he examined the accounts and sold the prizes of colony captains.
In 1778 the general assembly gave him additional authority, the management and direction, as marine agent, of all armed vessels belonging to or fitted by the state. He corresponded with Washington, who once honored him with a visit. He served two terms as deputy to the assembly.
Meanwhile, beyond the commissions he took on the naval business he transacted, he had an eye to his own advantage. Where once he ran a fleet of trading vessels, he now owned a string of privateers, the most pretentious, the General Putnam, being a brig of twenty guns. His gains by these means scarcely compensated, however, for the losses he sustained when Benedict Arnold's attack on New London in 1781 destroyed his wharves and warehouses. In that same year he opened commercial connections with Amsterdam merchants.
In April, 1782 while hunting ducks off Lester's Rocks, Shaw was accidentally wounded by a discharge from his own gun. Three days later he died.
A typical Connecticut Yankee, shrewd, close, a stickler for his bond, a curt letter-writer, he adhered rigidly to the high ethical code prescribed by the commerce of his age.
He was married, July 20, 1758, to Lucretia, daughter of Daniel Harris and widow of Josiah Rogers. In December of 1782 his wife died from an infection caught from the sick prisoners she nursed. He left no children.
