Defined by the chaos of a presidential campaign under literal siege, an unpopular foreign war and the compound tragedies of the assassinations of Martin Luther King Jr. and Robert F. Kennedy, the year 1968 was a pivot point in the national life—the year America almost stopped being America.

Part of that upheaval was cultural. The high priests and priestesses of rock culture, cued by the unrest around them, created brilliant, jagged music that was a barometer of the time.

Electric Ladyland, released by the Jimi Hendrix Experience in October 1968, was a record that, thanks to the restless creative spirit of the guitarist Jimi Hendrix, both expanded the culture's emerging vocabulary and, in a time when black popular music was largely locked in the confines of three-minute, verse-chorus-verse construction, widened the popular perception of what black music could be.

A brilliant blend of soul, jazz improvisation, blues and psychedelia, Ladyland still commands the popular fascination for the way it persisted in modern pop culture. Four decades after its release, and almost 40 years after Hendrix's death in September 1970, Hendrix himself endures as a musical and spiritual template for everyone from Michael Jackson to Prince to Lenny Kravitz—and a source of inspiration for the diverse crew of musicians now touring the United States performing music Hendrix wrote and inspired.

Jimi knew what was at stake in early 1968. Just the year before, he'd been all but hailed as a superstar with the release of the debut Experience album, Are You Experienced? That record, plus a transcendent set at the 1967 Monterey Pop Festival cemented the group, and Hendrix, in rock's top ranks.

With the Experience trio format wearing thin, and eager to experiment with other musicians playing other sounds, Hendrix took charge of the Ladyland sessions. Ladyland was the first Hendrix/Experience album fully realized with a galaxy of outside players participating, from homeboy compadres (Buddy Miles and Larry Faucette) to psychedelic rock royalty (Jack Casady and Al Kooper).  But it was Jimi's show. His insistence on laying down the tracks in his head and his heart, the way he heard them, led to the recording of one of rock music's defining documents, as sonically adventurous as anything in the halcyon era of the 1960s, and the years since then. Hendrix's brilliant reimagining of Bob Dylan's "All Along the Watchtower" is No. 48 in Rolling Stone's listing of the 500 greatest songs ever recorded.

He's been gone more than a decade longer than he was alive, but Jimi Hendrix is the touchstone for events in present day. His estate has been the subject of family disputes for years. Experience Hendrix LLC, the western Washington state company that monitors the legal aspects of Hendrixiana, offers a range of goods in an online catalog. The guitarist's name and likeness have been licensed for hundreds of products available on the company's Authentic Hendrix Web site.

But fans these days aren't lining up for lava lamps and limited-edition figurines; the Hendrix faithful are snapping up tickets for the Experience Hendrix 2008 Tribute Tour, which began on Oct. 15 and continues for 19 dates around the country.

The tour's players are testimonial to the breadth of Hendrix's influence: blues champions Hubert Sumlin and Buddy Guy, phenom Kenny Wayne Shepherd, pedal-steel guitar virtuoso Robert Randolph, former Rolling Stone Mick Taylor and Experience veterans Mitch Mitchell and Bill Cox are just some of those featured on the tour, which runs into November.

The apple of invention doesn't fall far from the family tree: The musical sound of Jimi Hendrix's younger brother, Leon, a guitarist in his own right, borrows from his more illustrious brother. Tricked by the Sun, a record Leon Hendrix plans to release independently, bears a sound drenched in the heavy metal style with a strong dose of electric blues—very much in keeping with the tradition Jimi fathered.

And that sense of brilliantly reconfigured tradition—of passing something on—is what Electric Ladyland celebrates. That's the reason why Jimi Hendrix still breathes in our culture. Strip away the trappings of psychedelia, the artifice of the studio, the merchandising of his identity, the adulation of millions … and it all comes down to the music of a rare, gifted soul.

"You still hear Beethoven and Mozart because it was original music, lasting music," Leon Hendrix told me in an interview last year. "A lot of people make music but Jimi made music that lasts. There's people on my Web site saying, 'Can I get tickets to your brother's concerts? When is he coming to town?' They don't know he's been dead for 37 years."

"Good music is forever."

Michael E. Ross is a West Coast journalist who blogs frequently on politics, pop culture and race matters at Culchavox ; and is a periodic contributor to PopMatters. His writing has appeared in msnbc.com, Entertainment Weekly, The Loop and The New York Times.