Everette Beach Long, one of America's foremost experts on the Civil War, was born 24 October 1919, in Whitehall, Wisconsin to Cecil Everettee and Florence (Beach) Long. He attended Miami University in Oxford, Ohio from 1937 to 1939 and Northwestern University from 1939 to 1941. In 1942, E. B. Long married Barbara Conzelman.

E. B. Long began his career working for the Chicago Bureau of the Associated Press for eight years and as an associate editor of American Peoples Encyclopedia. After this time, he decided to devote himself to historical research and teaching. "I got interested in the Civil War as a hobby," he explained. "Then it became an avocation, then a way of life."Long was the director of research for Doubleday's multi-volume Centennial History of the Civil War, written by Bruce Catton from 1955 to 1965. He was a member of the advisory council of the National Civil War Centennial Commission. Long was a member of the Chicago Civil War Round Table and served as its president from 1955 to 1956. He was a member of the Friends of the Chicago Public Library and was its president in 1960.

E. B. Long's list of honors and awards includes a D. Litt. from Lincoln College in 1961 and the Harry S. Truman award for Civil War scholarship in 1964. He received the Award of Merit from the Illinois Civil War Centennial Commission in 1963 and 1965, the Award of Commendation from the Oklahoma Civil War Centennial Commission in 1965, and the Centennial Medallion from the U. S. Civil War Centennial Commission in 1966.

The writings of E. B. Long include As Luck Would Have It co-written with Otto Eisenschiml and published by Bobbs in 1948, as well as The Civil War, A Picture Chronicle, Vol. 2, co-written with Ralph Newman and published by Grosset in 1956. He was the editor, with Ralph Newman, of The Civil War Digest which was published by Grosset in 1960, and a contributor to Lincoln for the Ages which was published in 1960 by Doubleday. E. B. Long was the editor and wrote the introduction to Personal Memoirs of U. S. Grant and History of the Civil War, 1861-1865, and wrote the introduction to The Post Reader of Civil War Stories. Long wrote the abridgement and the introduction to Stonewall Jackson and the American Civil War, by George F. R. Henderson, and the introduction to Four Years in Rebel Capitals, by Thomas Cooper De Leon. He was a member of the editorial advisory board of Civil War History, and of the bibliographical committee of Lincoln Lore. In 1971, Doubleday published The Civil War Day by Day, Long's chronology of the American Civil War.

In his research for Centennial History of the Civil War, Long compiled over nine million words of notes. Much of this material was obtained from original manuscripts, diaries, and records, and was gathered during trips throughout the country. He visited over 125 libraries, universities, and archives and traveled over 60 thousand miles. In 1966, Doubleday presented his research notes to the Library of Congress. He owned more than five thousand books, most of them about the Civil War or American History.

E. B. Long died on 31 March 1981 in Chicago, Illinois, the day after the publication of his last work, The Saints and the Union: The Utah Territory in the Civil War.