Composing is like breathing. It's just something I do, like a hobby, really...or an addiction

The world's most performed classical composer, a small, black-suited figure with a mop of white hair and mutton-chop whiskers, stands on the huge Brucknerhaus stage, almost invisible among the sea of musicians.

- Karl Jenkins

Karl Jenkins is conducting his latest epic, One World, for the annual UNESCO Concert for Peace.

There are at least 700 musicians from the World Orchestra and Choir for Peace on the stage and balconies, and hundreds more singers from the Stay At Home Choir visible on the huge bank of screens above the musicians. The audience in the hall numbers well over 1,000, and the number watching the live stream, still available on YouTube, is nearly 200,000.

Jenkins, who has just celebrated his 80th birthday in February, has become the international composer of choice to mark global events, particularly those involving conflicts and disasters. His millennium commission, The Armed Man: A Mass for Peace, was dedicated to the victims of the Kosovo conflict but could equally be applied to the war in Ukraine and the victims of the Gaza conflict. The texts include the Islamic Call to Prayer, as well as words and music from Western Christian and Hindu sources.

One World looks at the destructive effect of humans on the natural world, but also offers a vision of a peaceful and egalitarian planet that treats nature with respect. It draws inspiration from texts such as the Bible and the Hindu Gayatri Mantra as well as including poetry by Shelley, Khalil Gibran and Jenkins' wife, the composer and librettist Carol Barratt.

He was knighted in 2015 for services to music, yet this quietly spoken Welshman keeps a low profile - so much so that he caused excitement at the Coronation when the papers suggested he might be the Duchess of Sussex in disguise.