For almost three decades beginning in 1936, many African-American travelers relied on a booklet to help them decide where they could comfortably eat, sleep, buy gas, find a tailor or beauty parlor, shop on a honeymoon to Niagara Falls, or go out at night. In 1949, when the guide was 80 pages, there were five recommended hotels in Atlanta. In Cheyenne, Wyo., the Barbeque Inn was the place to stay.

A Harlem postal employee and civic leader named Victor H. Green conceived the guide in response to one too many accounts of humiliation or violence where discrimination continued to hold strong. These were facts of life not only in the Jim Crow South, but in all parts of the country, where black travelers never knew where they would be welcome. Over time its full title  “The Negro Motorist Green Book: An International Travel Guide”  became abbreviated, simply, as the “Green Book.” Those who needed to know about it knew about it. To much of the rest of America it was invisible, and by 1964, when the last edition was published, it slipped through the cracks into history.

Until he met a friend’s elderly father-in-law at a funeral a few years ago, the Atlanta writer Calvin Alexander Ramsey had never heard of the guide. But he knew firsthand the reason it existed. During his family trips between Roxboro, N.C., and Baltimore, “we packed a big lunch so my parents didn’t have to worry about having to stop somewhere that might not serve us,” recalled Mr. Ramsey, who is now 60.

He is among the writers, artists, academics and curators returning a spotlight to the guide and its author, emblematic as it was of a period when black Americans  especially professionals, salesmen, entertainers and athletes  were increasingly on the move for work, play and family visits.