It should come as no surprise that Levon Helm was working right up until his untimely passing on April 19 -- or that one of his final studio performances was delivered for a very good cause. Along with an impressive all-star cast that included Rosanne Cash, Donald Fagen, Warren Haynes, Eric Burdon, Marianne Faithfull, Taj Mahal, and many more, Helm contributed to 'Toast to Freedom,' a new single recorded in honor of Amnesty International's 50th anniversary.

Written by producer Carl Carlton and Helm's frequent musical partner Larry Campbell, and largely recorded at Helm's studio in Woodstock, NY with producer Bob Clearmountain, 'Toast to Freedom' is being released in conjunction with World Press Freedom Day, and is available at the Toast to Freedom website.

"Levon was one great soul," said entrepreneur Jochen Wilms, who helped coordinate the recording. "I am so grateful we got to work with him, his outstanding band and team in his barn in Woodstock. He was an inspiration and our muse. The song 'Toast To Freedom' is dedicated to Amnesty International but in a certain way is now a 'Toast To Levon' and a celebration for him as well: Truth, heart and soul were always part of Levon's DNA and are the essential basis of Amnesty International and our project. We will miss him and love him forever."

Select artists from the sessions, which incorporated contributions from more than 50 musicians, appeared last night (May 3) on 'The Tonight Show with Jay Leno' to perform the song and help raise awareness for the cause. Watch the 'Toast to Freedom' video below, along with a making-of clip.

'Toast to Freedom' music video

The making of 'Toast to Freedom'