Kris Kristofferson must be fairly unusual among US stars. He does, after all, have a Masters degree from Oxford. In 1958, still unknown as a songwriter, far less the actor who would play with Barbra Streisand in A Star is Born (1976), Kristofferson came to Oxford to study English literature. While there, he was galvanised by the words of William Blake, the poet and painter, after whom he would name his eighth child.
"Blake thought that if you were called by the Divine to be creative, you were obligated," Kristofferson says. "He said that if you buried your talent, sorrow and desperation would pursue you throughout life, and after death, shame and confuse you until eternity. For a young guy like me who wanted to be creative against everybody else's advice, that was powerful stuff."
Now, Kristofferson can look back on more than 60 movie roles and the authorship of such country classics as "Help Me Make It Through the Night", and "For the Good Times". More than 500 artists have tackled tunes from his gritty, gospel-influenced repertoire.
An estimate of how much Kristofferson's songs have earned him is difficult, but the revenue must be colossal. Some find his own husk of a voice testing to listen to; others see it as a lived-in badge of honour. He's a bit like Dylan, then. Or Neil Young, or Willie Nelson.
He is here to perform at Symphony Hall in Birmingham in support of a "best of" album. Apart from his manager and third wife, Lisa, he seems to be travelling alone.
Kristofferson looks like an unreconstructed version of his younger, wilder self. Now 68, he's wearing cowboy boots and a black shirt tucked into black jeans, but his alcoholism and the triple-heart bypass five years ago - "they sawed me open and it slowed me right down" - have left their mark. He's still handsome, though, the white teeth and blue eyes pretty much unchanged.
Why is he back? "I'd been off the road a while, and didn't miss it much," he says. "But then I did a solo gig in Nashville after Johnny Cash's funeral, and the songs seemed to have taken on a new resonance. Whether the world political situation has caused people to perceive what I'm writing differently, I don't know, but something has changed there, too. Earlier this year I sold out three nights at the Point in Dublin; I could never have done that in the Eighties or Nineties."
Kristofferson says the loss of Cash still "weighs heavy". It was Cash who introduced him at a gig at the Newport Folk Festival in 1969. "That performance is for ever etched on my memory, because it was the night of the first moon landing. After that, John kept a lyric of mine, 'The Golden Idol', in his wallet. He never recorded it, but just the fact that he was carrying it around was big for me."
The eldest of three children, Kristofferson was born in Brownsville, Texas. His father was an air force officer whose itinerant lifestyle eventually took the family to San Mateo, California. There, Kris was a Golden Gloves boxer and studied creative writing at Pomona College. But it was after he won his Rhodes scholarship to Oxford, he says, that his life bloomed.
"It exposed me to a lot of great literature, but more than that, I got to explore mainland Europe. I even ran into [Ernest] Hemingway at a bullfight in Spain. He was wasted, and it wasn't that long before he took his own life, but anyway, it was Hemingway..."
Before his time at Oxford, Kristofferson had enlisted in the US Army, but his active service was deferred until he finished his studies. He served in Germany, learning to parachute and fly helicopters, and encountering Johnny Cash when his hero flew in to entertain the troops.
His platoon leader was a cousin of the celebrated Nashville songwriter Marijohn Wilkin, who invited him to visit the country-music capital during a leave period in July 1965. Kristofferson opted to return there to work as a songwriter rather than to teach English literature at the West Point military academy. "Nashville was magical back then," he says. "Just two important streets: 16th and 17th Avenue South, and all the publishing houses and recording studios right there. Through Marijohn, I got to meet legends like Cowboy Jack Clement and Mel Tillis."
It was a great schooling, as was his time as janitor at Nashville's Columbia Studios. While there, Kristofferson finally met Cash in person, and the pair bonded after Cash intervened to prevent Kris's wrongful sacking. "By the time John started taping his TV shows at the Ryman Auditorium," Kristofferson says, "he was telling Bob Dylan and Joni Mitchell that my buddy Mickey Newbury and I were the best songwriters in Nashville. It wasn't true, but it was a great endorsement."
Having seen Kristofferson on Cash's TV show, the director Dennis Hopper offered him a bit part in his 1971 film, The Last Movie, and so began his acting career. The film was shot in Peru. It must have been a blast. "Are you kidding?" Kristofferson laughs. "All those Hollywood people in the cocaine capital of the world... It was insane. That was probably the craziest part of Dennis's life. Mine, too, perhaps."
And what of A Star is Born? It was a box-office smash, but the critics panned it. "They had in it for Barbra," he says. "They thought she was the star pushing past her boundaries and controlling every aspect of the film, but I thought she did great. It changed everything for me, too. Suddenly, my band and I were playing stadiums, and they were like, 'Wow! What happened?' It was like stepping on to a very beautiful roller coaster."
The late Seventies and Eighties proved more testing. Kristofferson had married his second wife, the singer-songwriter Rita Coolidge, in 1973. That year the couple won a Grammy for their duet on "From the Bottle to the Bottom", but by 1979 they were divorced. Kristofferson's alcohol and drug binges were reportedly a major factor. "When Rita and I split, it was devastating to me. It happened at the same time as [the panned movie] Heaven's Gate, and all the other disasters in my life. But sometimes the end of something is the beginning of something else. I've been with my current wife, Lisa, for 21 years."
Musically, too, Kristofferson was adrift. Politically-outspoken albums such as Repossessed (1986) and Third World Warrior (1990) had left him "pretty much unmarketable. Because of the stances I was taking - for human rights in Nicaragua, for example - country radio wouldn't touch me."
But then Cash intervened, helping to launch a renaissance Kristofferson is still enjoying. "He wrote a letter to Country Music magazine, defending me like he'd defended Bob Dylan when people criticised him for going electric. 'Leave Kris alone,' he told them, 'He knows what he's doing.' John was like a god to them, so they could hardly ignore him."
While many US artists are wary of making statements that might be deemed "unpatriotic" for fear of harming their sales, Kristofferson continues to wade right in. Asked what he thinks of the Bush administration's foreign policy, he is forthright. "I think it's the worst thing that's happened on my time on the planet. To me, it seems contrary to everything we should be doing.
"We should be respecting international law. We should be co-operating with our allies. We should be using diplomacy rather than violence. We tried to make the UN irrelevant in our actions in Iraq. And to me the unilateral military action that's going on... it's like we're doing it because we can, not for the purported reasons."
Kristofferson is looking forward to going home to Hawaii. "I've got a lot of grass to mow, so I can't wait to jump on my tractor with a bit of Steve Earle or Johnny Cash on the headphones."
But what of his fabulously rich and eventful life: the music, the films, the slot on The Muppet Show in 1978? Where's the autobiography? "I am negotiating a deal," he says, "but I'm too busy living life to pull up and start writing. I'll get round to it eventually, though; I want the kids to understand who the old guy who sits drooling in front of the TV is."
'The Essential Kris Kristofferson' is out now on Columbia/Legacy