CHELSEA Clinton, Jeremy Corbyn, the family of Nelson Mandela and a host of writers, thinkers, poets and politicians from Scotland and abroad are to appear at this year's Edinburgh International Book Festival.

The annual festival is altering its footprint in the capital with new and larger 750-capacity main tent theatre, up from 600 seats, in Charlotte Square, a larger Spiegeltent, and a sustained expansion into George Street, where the festival will have three tented venues.

This year the festival has the theme of Freedom, and it has with money from the Scottish Government's Expo Fund has commissioned a new book, featuring 52 authors from 25 countries, including thirteen from Scotland, including a series of literary ruminations on the theme.

Nick Barley, the director of the festival, said the programme's theme of Freedom touches on how significant current affairs - Brexit, the Presidency of Trump, and the continued power of Russian leader Vladimir Putin - came to be.

The Freedom Papers will tackle LGBT issues, race, religion, immigration, disability, education and technology and encompasses prose, poetry and illustration, and it will be published with the literary magazine Gutter in July.

Ms Clinton, the daughter of President Bill Clinton and Presidential candidate Hilary Clinton, will be appearing at two events, the first with Sally Magnusson, where she will talk about her book She Persisted Around the World.

Several veteran rockers are appearing: Brian May, the guitarist from Queen, will be in attendance, as will Bruce Dickinson of Iron Maiden, Viv Albertine of The Slits, and Brett Anderson of the Britpop band Suede.

May will be appearing with Professor Roger Taylor - ironically, not the drummer from Queen, but an academic with the same name - to talk about a Scottish pioneer of photography, George Washington Wilson, who made innovations in stereoscopic photography.

The actress Rose McGowan, a key figure in a recent revelations of abuse in Hollywood, will also be appearing to talk about her book Brave.

Corbyn, the Labour leader, will be in conversation with Yanis Varoufakis, the former finance minister of Greece, who is a guest selector alongside Adele Patrick of Glasgow Women's Library, Afua Hirsh, Tania Kovats and Ehsan Abdollahi.

Varoufakis will be exploring the question of "whether the current form of globalised capitalism is forcing democracy towards its ultimate demise".

The First Minister, Nicola Sturgeon, will be in conversation with noted Scottish writer Ali Smith.

This year marks the 100th anniversary of the birth of Nelson Mandela, and the festival will host his daughter Zindzi and great-grandchildren Zazi and Ziwelene to talk about his life and legacy.

Other names at the festival, which runs from August 11-27, include Susan Calman, Ruby Wax, Susie Orbach Philip Pullman, Cressida Cowell, Matt Haig, Greg Wise, Robert Peston, Gina Miller and Jo Nesbo.

As reported in The Herald last week, the festival will also be staging, with the Lyceum, Doctors of Philosophy, the only play written for the stage by Muriel Spark.

Writer Chris Brookmyre and his wife Marisa Haetzman will launch their new crime novel under the pen name Ambrose Parry.

The illustrator Alan Lee has provided the images for the "last ever" Tolkien story, The Fall of Gondolin, which has its global launch at the Festival.

Ticket for all events go on sale on June 26.