In the Footsteps of George Borrow: A Journey Through Spain and Portugal by Guy Arnold
George Borrow, who made the journey in the 1830s.
This puts the book in the same genre as William Dalrymple's wonderful In Xanadu (in which Dalrymple retraces Marco Polo's route to China) and his even more brilliant From the Holy Mountain (in which he follows in the footsteps of the Byznatine monk John Moschos). Sadly, this book doesn't measure up to either of those works.
I love George Borrow. I have read three of his books - Lavengro and The Romany Rye describe his dealing with gypsies in England, while The Bible in Spain relates how he went around the Iberian peninsula distributing New Testaments on behalf of the British and Foreign Bible Society. This is the book that Arnold is interested in, as he retraces Borrow's steps.
Arnold admits that he is irreligious, and that colours his interpretation of Borrow. He tends to take a cynical view of Borrow's work, and suggests that The Bible in Spain is not the book of a missionary, but "the highly coloured, exciting work of an adventurer" (p. 175). Arnold argues that Borrow "employs the piety of language expected of religious people - after he had learned or assumed it for the benefit of his paymasters, the Bible Society" (p. 168).
Arnold's lack of knowledge in Christian matters comes out in his misunderstanding of scholastic philosophy (p. 160) and his notion that G. K. Chesterton's poem Lepanto is written from a "cruelly partisan" Protestant view (p. 135).
I can't really recommend this book. Rather, I urge the reader to instead read William Dalrymple or George Borrow, or preferably both.