If you started reading the series in the ‘60s, odds are it was John Broome. He didn’t write every Green Lantern story of Hal Jordan’s first decade, but he was there for the character’s introduction (in September-October 1959’s Showcase #22), and he lasted until March 1970’s Green Lantern #75.
If you joined the Corps in the the ‘70s, your Green Lantern writer was Denny O’Neil, who had already written a few GL stories before getting the regular gig with the landmark Issue 76. He guided the feature through some rocky patches — including the book’s cancellation, its time as a backup feature in The Flash and its 1976 relaunch — before finally taking a bow with June 1980’s Issue 129.
The ‘80s saw a parade of writers, including Marv Wolfman, Mike Barr, Len Wein and Steve Englehart (and in GL’s time as an Action Comics Weekly feature, Jim Owsley/Christopher Priest and Peter David). Each made his own contribution, be it Hal’s exile from Earth, John Stewart’s star turn, the Guardians’ sabbatical, or the enigmatic Lord Malvolio. The early ‘90s belonged to the neo-Silver Age stylings of Gerard Jones, and the balance of the decade was all Ron Marz and Kyle Rayner. Starting in 2000, Judd Winick took on Kyle for three years, then Ben Raab wrote a few issues, and Marz came back for one last crack at his creation.