On September 18th this year, the voters of Scotland will decide in a referendum whether they want their nation henceforth to be independent of the United Kingdom, or remain within the union that has bound Britain together since the Act of Union of 1707.

In "Acts of Union and Disunion", Linda Colley, Professor of History at the University of Princeton, examines the forces that bind together the diverse peoples, customs and loyalties of the United Kingdom. And the often equally powerful movements that from time to time across the centuries threaten to pull Britain apart.

In tonight's third and final Omnibus Edition, Professor Colley explores Britain's relationships with North America, with Europe, with its far-flung expatriate Britons and its own (unwritten) Constitution. She then posits some possibilities about how the UK may develop in the years following next September's Independence vote in Scotland...

Producer: Simon Elmes. Show less