Much of O'Reilly's drive and capacity for reinvention comes from the fact that he is illegitimate - though he only found out about this when he was told by Jesuit priests at his school, Belvedere College. His father, he learned, had a secret wife and family. Through hard work, and probably a fevered effort to reinvent himself, he won a scholarship to read law at University College, Dublin, where his rugby caught the attention of the Irish selectors. From his rugby success, he moved into the food business, first making his name in the Sixties when he rebranded Ireland's dairy butter, Kerrygold. In 1969 he made the gamble of his career when he was offered a job by the Irish government but instead went to work for Heinz in England. Within four years he had moved to Pittsburgh to run the global Heinz empire, becoming CEO in 1979 and chairman a decade later.