In 1933, he was appointed full professor at Yale University and four years later, in 1937, he married Kirsti Ore, who was the sister of his Yale colleague, the mathematician Oystein Ore. Kirsti Hille wrote the article after the death of her husband. Kirsti and Einar had two children, both sons. Hille was appointed director of graduate studies in 1938 and he held this position, and his chair, at Yale until he retired in 1962.
Sa 1933, siya ay hihirangin ng buong propesor sa Yale University at apat na taon mamaya, sa 1937, siya na may-asawa Kirsti ng mineral, na ang mga kapatid na babae ng kanyang Yale kasamahan, ang dalubbilang Oystein Ore. Kirsti Hille wrote ang article pagkatapos ng kamatayan ng kanyang asawa. Kirsti at Einar nagkaroon ng dalawang anak, parehong anak. Hille ay hihirangin direktor ng graduate studies sa 1938 at siya gaganapin ito sa posisyon, at ang kanyang mga silya, at Yale hanggang siya ay nagretiro sa 1962.