His father, Charles, was a porter at the Home Office, and his mother, Mary (nee Donovan), was an administrative assistant.
He was educated at the Catholic St Benedict’s school in Ealing and Worcester College, Oxford where he received a BA in Modern Languages.
O'Shaughnessy published a number of books and articles focusing on Latin American politics, making many trips to Central and South America to study social and political issues.
[4] O'Shaughnessy won several awards, including two British Press Awards, the 1986 Maria Moors Cabot prize for journalistic contributions to inter-American understanding and the Wilberforce Medallion from the city of Hull.
He was recognised by the Columbia University Graduate School of Journalism in the United States.