The award-winning historian delved into the letters that form his latest book, Written in History: Letters That Changed the World.
"There's a truth in letters," he said, "The fact is: they represent a moment in time."
From Stalin and Trump to T. S. Elliot and Orwell, his anthology studies history through the lens of correspondence. He looks at letters through the ages as they survive the genesis of the telephone and the digital age.
"What I wanted to do was to make sure that the whole of human drama was played out in some sort of delicatessen of words," he said.
His talk was punctuated with heartbreaking and poignant readings of letters across the world, including one that survived the Holocaust. "It's not overly emotional," he said, "and then all the more emotional for it."
He also read a note from Alan Turing before his suicide that ended in the line: "Yours in distress, Alan."
His book also features correspondence between Leonard Cohen and his dying lover, Marianne. Cohen writes: "But now, I just want to wish you a very good journey. Goodbye old friend. Endless love, see you down the road.”
"All of them, I believe, changed the world somehow," said Sebag Montefiore.
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Photograph by Chris Athanasiou.