It is impossible to thank all those who have helped me with this project and I apologise to all those who I fail to mention here. Transnational history requires reliance on the generosity of strangers and I have encountered considerable amounts of this in my travels and enquiries in foreign archives and libraries.
I feel a particular privilege working in the intellectually stimulating and friendly atmosphere of the history department at Newcastle University. I could not put a price on the support and encouragement of Joan Allen, Claudia Baldoli, Lara Cook, Martin Farr, Tim Kirk, Alejandro Quiroga, David Saunders, Felix Schulz and Samiksha Sehrawat. Members of the Labour and Society Research Group – Máire Cross, Daniel Laqua and Nicole Robertson – have provided a vibrant and supportive environment for labour history. I must thank also Hester Barron for her kindness. Old friends Steve Cannon and Tony Dabb have also lent a hand with reading and criticism of my manuscript. I would also like to take the opportunity to thank Paul Preston with help in tracking down more elusive Spain-related sources. The editorial board at the International Review of Social History and anonymous readers provided insightful criticism.
I owe the greatest debt to two people. David Reid accumulated materials in the expectation of publishing a biography that never materialised. He allowed me access to these materials when he was very ill. They are now deposited in Newcastle University Special Collections. His spade work and generosity was of considerable help. And finally, thanks to Christine.