Patrick O'Connor is a pseudonym for Leonard Wibberley, a popular author of adult and children's books in the 1950s. His work is hard to find nowadays; too bad, because I remember enjoying many of his stories.
I remember liking this book so much that when my high school English teacher required that we compare our favorite book to the one we had to write a book report for, I compared The Last Temptation of Christ to this book: it's more exciting, although Kazantzakis' book is more complex.