Professor Winthrop was one of the foremost men of science in America during the 18th century, and his impact on its early advance in New England was particularly significant.

[1] He also had a decisive influence in the early philosophical education of John Adams during the latter's time at Harvard.

[3] He traveled in a ship provided by the Province of Massachusetts—probably the first scientific expedition ever sent out by any incipient American state.

During the nine months in 1775–1776 when Harvard moved to Concord, Massachusetts, Winthrop occupied the house that would become famous as The Wayside, home to Louisa May Alcott and Nathaniel Hawthorne.

Additionally, he was actively interested in public affairs, was for several years a judge of probate in Middlesex County, was a member of the Governor's Council in 1773–74, and subsequently offered the weight of his influence to the patriotic cause in the Revolution.