Son of George Chychele Waterston aka G. Chychele Waterston or George C. Waterston (b. Leith, Scotland, 20 May 1904, d. Sharon, Connecticut, 13 May 1995), diplomat, linguist, and wife (m. Chestnut Hill, Massachusetts, 6 July 1935) Alice Tucker Atkinson (b. Brookline, Massachusetts, 10 Dec 1905, d. Sharon, Connecticut, 29 Nov 1993), and maternal grandson of musician Robert Whitman Atkinson (b. Heath Street, Brookline, Massachusetts, 14 Dec 1868, d. Mattapoisett, Massachusetts, 21 Aug 1934), Harvard 1891, and wife (m. Philadelphia, Pennsylvania, 5 Mar 1904) Elizabeth Bispham Page (b. Philadelphia, Pennsylvania, 27 Mar 1875, d. Middleborough, Massachusetts, Jan 1962).
Three of his children followed him into the show business industry: Elisabeth Waterston, Katherine Waterston, and James Waterston.
Voices the TV ad for "The Nation", a political commentary magazine with a progressive viewpoint. Included is the line "The Nation gives you that liberal media slant you can't get anywhere else".
Was good friends with Bruce Lee.
Was nominated for Broadway's 1994 Tony Award as Best Actor (Play) for playing Abraham Lincolnin a revival of Robert E. Sherwood's "Abe Lincoln in Illinois.".
Winner of the 2003 Richard Nelson Current Award of Achievement, awarded annually by the Lincoln Forum.