Bachelor of Arts, Harvard, 1891, Arts Doctorate. (honorary), 1949. Studied in New York City, Paris, also with Doctor Denman West. Ross, Cambridge, Massachusetts, Carl G. Cutler, Boston.
He maintained a studio in the Fenway Studios building in Boston from 1906 to 1962. He painted over 800 portraits in a direct style with a palette gradually lightening through his career. Many of his paintings were commissioned by United States East Coast institutions, especially Harvard University, where he acted as house portraitist.
Among his sitters were Oliver Wendell Holmes, Calvin Coolidge, and John Masefield.
He began to draw for the Harvard Lampoon upon his entrance to Harvard in 1888, and in 1891, he moved to New York to study at the Art Students" League where he worked with John Henry Twachtman and H. Siddons Mowbray. In the late 1890s he worked in Cambridge, Massachusetts and showed his paintings in New York at the Society of American Artists and also in Boston.
He returned to Europe in 1901, where he visited Spain to study the painting of Velázquez and El Greco and traveled through Brittany, and the Netherlands to see portraits by his "heroes", Frans Hals and Rembrandt. He exhibited regularly in the national annuals and at several Boston and New York galleries.
His watercolors were described as "modern" in the press and he exhibited three oils in the 1913 Armory Show.
Instead of allying himself with the local established painters, Hopkinson showed his work with the "Boston Five", a group of young watercolorists though he continued to paint in oil for an elite clientele. In 1919 the National Art Commission selected him to paint some of the participants of the Peace Conference at Versailles, France. In 1927 he was elected into the National Academy of Design as an Associate member and became a full Academician in 1929.
In the mid-1920s, Hopkinson took on a young Boston painter Pietro Pezzati as his assistant, who worked with him at his Fenway studio.
Hopkinson would pass on his studio to Pezzati when he died in October 1962, in Beverly, Massachusetts.
Fellow American Academy Arts and Science, National Association Portrait Painters. Member American Academy Arts and Letters, National Institute Arts and Letters, American Water Color Society, Massachusetts History Society, Phi Beta Kappa (honorary).
Married Elinor Curtis, March 14, 1903. Children: Harriot (Mistress Alfred Rive), Mary (Mistress John H. Gibbon, Junior.