Here's some more info about that Allen Toussaint piece, from the No Depression website. Incidentally, the track is not on the album seen in the clip.
Toussaint had been coaxed back into action a few months before the hurricane by Joe Henry, an inspired songwriter and recording artist in his own right, who seems to have shifted his emphasis to production in general and making contemporary-sounding soul albums with classic artists in particular. Following his Grammy-winning work with Solomon Burke, his grand vision at the time was a project titled I Believe To My Soul, including Ann Peebles, Billy Preston, Mavis Staples and Irma Thomas, along with Toussaint as not only a featured artist but pianist throughout the sessions.
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By the time I Believe To My Soul was released to rave reviews that fall, the hurricane had already hit, and proceeds from the album were directed toward Katrina relief. Among the subsequent benefit releases the disaster inspired, the best was Our New Orleans 2005 on Nonesuch, which quickly reunited Henry with Toussaint and Irma Thomas. Opening the album is Toussaint’s rendition of “Yes We Can”, the first time he’d recorded the number on his own, with its lyric of resilience sounding all the more timely in light of current events. The album’s highlight was his solo instrumental recasting of Professor Longhair’s uptempo anthem “Tipitina” into the mournful, minor-key “Tipitina And Me”.
“Professor Longhair was so vital to me,” says Toussaint. “I call him my Bach of Rock and consider him as important as the classical composers are in their field. And he had so many different periods, any one of which you could build a life on, taking it into all sorts of different things. After ‘Mardi Gras In New Orleans’, which is somewhere between rock and rumba, he came up with ‘Big Chief’, and I can’t imagine where else that kind of piano could come from. It’s unrelated to anything else I’ve ever heard. And in the middle of it all, ‘Tipitina’ is, as far as I’m concerned, the cornerstone of Professor Longhair.”
Perfect in itself, Toussaint’s elegant adaptation of his hero’s signature song provided the breakthrough for the artistic collaboration with Costello that carried The River In Reverse beyond the initial songbook concept. “When we started writing some songs, to be honest, we were almost too polite about who would go first,” says Costello. “And then I came up with the notion of writing lyrics to this beautiful version of ‘Tipitina’ that Allen had done. I said that this really paints a picture in my head, so I went home that night and wrote ‘Ascension Day,’ and that seemed to really break open the collaboration.”