Bob Geldof wasn’t on board, though he should have been. Hard-Fi, the Magic Numbers and Flea from the Red Hot Chilli Peppers all were, having hopped on at Lagos, Nigeria. Others — The Aliens, Get Cape Wear Cape Fly and US beatboxer Scratch — had alighted at Kinshasa in the Congo. Many started out in Bamako, Mali, and went on to Glastonbury and Liverpool.

It’s taken Africa Express three years to reach London. But last night’s star-studded and surprisingly ego-less marathon was worth the wait.
Blowing a melodica instead of a whistle, Damon Albarn was — as he has always been — a sort of unofficial conductor. Squeezed side-stage with many of the 140 African and Western musicians who had turned up for this musical extravaganza, he kept a relatively low-key profile.

Having co-founded Africa Express as a riposte to Sir Bob (who largely ignored African musicians when programming the London Live 8 concert for Africa in 2005), Albarn seemed more intent on keeping things moving. “We’re making this up as we go along,” he confessed a few hours in.

Africa Express prides itself on stopping at unexpected places. This old variety theatre with its gilt and blood-red interior was a fitting venue for an anything-goes show that celebrates the music of Africa and teams it with sounds from the West. There’d been minimal rehearsals earlier in the day: Algerian rai king Rachid Taha ran through The Cure’s Killing An Arab with oud player Mehdi Haddab, Nigerian singer Ayo and Sheffield’s Reverend and the Makers. The Magic Numbers’ Romeo Stodart knew he’d be peeling off guitar licks with Amadou Bagayoko of blind Malian duo Amadou and Mariam, having already done so in Lagos.

Some of the bigger acts got three songs each, during which other musicians — rappers, percussionists, guitarists, more rappers — added their bit. A few, both African and Western, struggled to find common ground. Most enhanced what was there in the first place. The Africans, long used to collaboration, fared best: n’goni maestro Bassekou Kouyate, Baaba Maal’s tama-talking drummer Massamba Diop and Baaba Maal himself. For a too brief moment Africa’s biggest female stars — Ami Sacko, Rokia Traore, Oumou Sangare (in robes and origami head wrap) — sang and formation-danced in a line.

More musicians crammed onstage as the six-hour show progressed: Afrobeat drummer Tony Allen, Miss Dynamite, MC Kano. Guitar god Johnny Marr came on around midnight. By 3am, and a cover of Fela Kuti’s Zombie, you could hardly see the stage for them. No Geldof, of course — but there’s room for all on the next one.

Africa Now, featuring many of the musicians from African Express, is at the Barbican tonight.