Helm, his longtime friend and producer Larry Campbell and a crew of musicians and technicians recorded the rhythm track for the new Amnesty International 50th anniversary commemorative song "Toast to Freedom" last summer and helped recruit stars like Ewan McGregor, Kris Kristofferson, Warren Haynes, Keb Mo, Carly Simon, Taj Mahal, Marianne Faithfull, Rosanne Cash and many others to join the effort.
"We were both really passionate about this cause," Campbell said in a phone interview. "When we recorded the original rhythm track for this, it was such a great day. Everybody was just completely in the spirit of the cause, the spirit of the song and the spirit of the music. One of the great things about working with Levon was he always made playing music a joyful event. And I know he wanted to see this thing through as far as he could."
Campbell said Helm had hoped to support the release of the album with live performances, including Thursday's debut on "The Tonight Show with Jay Leno," until his health failed. The pioneering drummer of The Band died April 19.
"He would've been out there on the Leno show had circumstances been different," Campbell said. "I just feel like his spirit was so much in line with the spirit of this song that he'll be missed when we do it.
The idea for the song began with producer Carl Carlton and entrepreneur and former music industry executive Jochen Wilms, who approached the human rights organization. Campbell said Carlton had much of the lyrical idea in place when he was invited to join the effort as co-producer and co-writer, adding music and a few suggestions. The story is based on the initial founding of Amnesty International by Peter Benenson. The British lawyer said the idea for the organization came after he read about a pair of Portuguese students who were arrested after making a toast to freedom in a bar.
After Helm and crew laid down the rhythm track an international recruitment process began. Other stars who joined the effort included Blind Boys of Alabama, Donald Fagen, Eric Burdon, Mahalia Barnes, Matthew Houck and Shawn Mullins.
They scheduled sessions when they could—a challenge, trying to coordinate four dozen artists. Some recorded overseas or on the West Coast. Others traveled to Helm's studio in Woodstock, N.Y.
"Then it came time to assemble the whole thing," Campbell said, "which was like putting together a 2,000-piece jigsaw puzzle because you want to make it sound like a complete work, something that's cohesive, and that it actually has the proper peaks and valleys and tension and release—all the things that make a good song."
The song continues a long relationship between Amnesty International and the creative community, which has helped spread the word of its mission almost from the start in 1961. McGregor said in a statement it is important to draw attention to the group's cause.
"For people that are in situations where they are denied any kind of voice ... those of us that have one should be loud on their behalf," he said. "We should be able to use our voice to draw attention to their struggle and to put pressure on the people that are oppressing them to let them know that we are here and we don't accept what they are doing. That it's not right and it's against our human code."
Amnesty International Secretary General Salil Shetty said in a phone interview from London that the group chose to release the song on Thursday, World Press Freedom Day, to support the cause of open media in places like Syria and China. And he sees much progress as Amnesty celebrates 50 years.
"If you take just one year, what's happened in the Middle East and North Africa, what those people are doing, I characterize that as a human rights revolution," Shetty said. "You cannot turn on the TV without seeing a discussion of human rights, which you'd never see before. It's a real resurgence of people power, the resurgence of ideals of justice, fairness and freedom."
Follow AP Entertainment Writer Chris Talbott at http://www.twitter.com/Chris—Talbott.