B.S., Harvard University, Cambridge, MA, 1856-1860; coursework, École nationale supérieure des Beaux-Arts, Paris, France, 1860-1865; in Paris, Richardson worked in the atelier of Louis-Jules André. He did not finish the curriculum at the Ecole due to his southern family's financial difficulties during the Civil War.

Richardson's great grandfather was the celebrated English theologian, philosopher and scientist Joseph Priestley (1733-1804). When his descendants came to the U.S. it appears that the Louisiana-based branch dropped an "e" from the last name. H.H. Richardson's maternal grandfather was William "Priestly." Richardson was raised in New Orleans, LA, and on the estate of his grandfather, Saint Joseph Plantation, Saint James Parish, LA. Richardson came to Harvard University in 1856 and stayed until 07/1859. He settled in Paris, France, in 09/1859, choosing that country spent the Civil War years in Europe, studying in Paris and elsewhere, and returned in 1865, at war's end. He got married in 1867 in Boston, MA, and set up his household on Staten Island, NY. He lived in this NY Borough until the Spring of 1874, when he relocated to Brookline, MA. Aside from numerous trips to visit projects, Richardson made the Brookline his home until his death in 1886.

Richardson married Julia Gorham Hayden in 01/1867 in Boston, MA.

Richardson and his wife Julia had six children, the first five of whom were born on Staten Island, NY: Julia Hayden Richardson (known as "Jula," born 1867), John Cole Hayden (1869), Mary Houghton (1871), Henry Hyslop (1872), Philip (1874); the last child, Frederick Leopold, was born in 1876 after the family had established itself in Brookline, MA. Jula married one of Richardson's employees, George F. Shepley, who later became a partner in Richardson's reorganized firm, Shepley, Rutan and Coolidge, after the master's death. According to James F. O'Gorman and Cervin Robinson, Philip and Frederick both went on to become architects and produced an unbroken line of practitioners stretching into the 21st century. (See James F. O'Gorman, H.H. Richardson and Cervin Robinson, "Living Architecture: a Biography of H.H. Richardson, [New York: Simon and Schuster, 1997], p. 78-81.)