Painter and art dealer.
Born in Boston. Apprenticed to Thomas Johnston, a Boston painter and engraver (1742). Resided in Surinam (1752-58) and Amsterdam (1758-64) before settling in London. Advertised exhibition of paintings to Franklin (1764). A portrait of Franklin’s sister- in-law Elizabeth, wife of John Franklin, has been attributed to Greenwood, and he may have painted the earliest known portrait of Franklin, although it is now generally attributed to Robert Feke. From c. 1776 on, Greenwood worked primarily as an art dealer rather than a painter.
Married; four sons.