The fans of the Grateful Dead, some of whom followed the band from concert to concert for years, are known as "Deadheads" and are known for their dedication to the band's music. Many referred to the band simply as "the Dead". As of 2003, the remaining band members have toured under the name "The Dead." Remaining band members Bob Weir and Phil Lesh formed "Furthur" in 2009. Drummer Bill Kreutzmann formed 7 Walkers with Malcolm "Papa Mali" Welbourne in 2009. The Grateful Dead's musical influences varied widely; in concert recordings or on record albums one can hear psychedelic rock, blues, rock and roll, country-western, bluegrass, country-rock, and improvisational jazz. These various influences were distilled into a diverse and psychedelic whole that made the Grateful Dead "the pioneering Godfathers of the jam band world." They were ranked 55th in the issue The Greatest Artists of all Time by Rolling Stone magazine.

The Grateful Dead began their career as The Warlocks, a group formed in early 1964 from the remnants of a Palo Alto jug band called Mother McCree's Uptown Jug Champions. The band's first show was at Magoo's Pizza in suburban Menlo Park, California on May 5, 1965. They were still known as the Warlocks at the time. The show was not recorded and not even the set list has been preserved. The band changed its name after finding out that another band of the same name had signed a recording contract. The first show under the new name Grateful Dead was in San Jose, California on December 4, 1965, at one of Ken Kesey's Acid Tests. Earlier demo tapes have survived, but the first of over 2,000 concerts known to have been recorded by the band's fans was a show at the Fillmore Auditorium in San Francisco on January 8, 1966. Later on that month, the Grateful Dead played at the Trips Festival, an early psychedelic rock show.

The charter members of the Grateful Dead were: banjo and guitar player Jerry Garcia, guitarist Bob Weir, bluesman organist Ron "Pigpen" McKernan, the classically trained bassist Phil Lesh and drummer Bill Kreutzmann (who then used the stage name Bill Sommers.) Lesh was the last member to join the Warlocks before they became the Grateful Dead: he replaced Dana Morgan Jr. who had played bass for a few gigs. With the exception of McKernan, the core of the band stayed together for 30 years, until Garcia's death in 1995.

The name Grateful Dead was chosen from a dictionary. According to Phil Lesh, in his biography (pp. 62), "...[Jerry Garcia] picked up an old Britannica World Language Dictionary...[and]...In that silvery elf-voice he said to me, 'Hey, man, how about the Grateful Dead?'" The definition there was "the soul of a dead person, or his angel, showing gratitude to someone who, as an act of charity, arranged their burial." According to Alan Trist, director of the Grateful Dead's music publisher company Ice Nine, Garcia found the name in the Funk & Wagnalls Folklore Dictionary, when his finger landed on that phrase while playing a game of "dictionary". In the Garcia biography, Captain Trips, author Sandy Troy states that the band was smoking the psychedelic DMT at the time. The term "Grateful Dead" appears in folktales of a variety of cultures. In the summer of '69, Phil Lesh told another version of the story to Carol Maw, a young Texan visiting with the band in Marin County who also ended up going on the road with them to the Fillmore East and Woodstock. In this version, Phil said, "Jerry found the name spontaneously when he picked up a dictionary and the pages fell open. The words 'grateful' and 'dead' appeared straight opposite each other across the crack between the pages in unrelated text." [grateful | dead]

Their first LP, The Grateful Dead, was released on Warner Brothers in 1967.

Classically trained trumpeter Phil Lesh played bass guitar. Bob Weir, the youngest original member of the group, played rhythm guitar. Ron "Pigpen" McKernan played keyboards and harmonica until shortly before his death in 1973 at the age of 27. Garcia, Weir and McKernan shared the lead vocal duties more or less equally; Lesh only sang a few leads but his tenor was a key part of the band's four-part vocal harmonies. Bill Kreutzmann played drums, and in September 1967 was joined by a second drummer, New York native Mickey Hart, who also played a wide variety of other percussion instruments.

The year 1970 included tour dates in New Orleans, Louisiana, where the band performed at The Warehouse for two nights. On January 31, 1970, the local police raided their hotel on Bourbon Street in the French Quarter, and arrested and charged a total of 19 people with possession of various drugs. The second night's concert was performed as scheduled after bail was posted. Eventually the charges were dismissed, with the exception of those against sound engineer Owsley Stanley, who was already facing charges in California for manufacturing LSD. This event was later memorialized in the lyrics of the song "Truckin'", a single from American Beauty which reached number 64 on the charts.

Hart quit the Grateful Dead in February 1971, leaving Kreutzmann once again as the sole percussionist. Mickey Hart rejoined the Grateful Dead for good in October 1974. Tom "TC" Constanten was added as a second keyboardist from 1968 to 1970, while Pigpen also played various percussion instruments and sang.

After Constanten's departure, Pigpen reclaimed his position as sole organist. Less than two years later, in late 1971, Pigpen was joined by another keyboardist, Keith Godchaux, who played grand piano alongside Pigpen's Hammond B-3 organ. In early 1972, Keith's wife, Donna Jean Godchaux, joined the Grateful Dead as a backing vocalist.

Following the Grateful Dead's "Europe '72" tour, Pigpen's health had deteriorated to the point that he could no longer tour with the band. His final concert appearance was June 17, 1972 at the Hollywood Bowl, in Los Angeles; he died in March, 1973 of complications from alcohol abuse.