Why have we never been told the full story of the ‘discovery of America’ before?  Of course the tale of Christopher Columbus has been told often, and – very occasionally, and mainly for children – so have the stories of John Cabot and Amerigo Vespucci, his fellow pioneers.  But those stories have been told separately until now, artificially bowdlerised into three different parts.  Toward the Setting Sun is a bid to tell it as one tale – as it originally was: of three young men, from the same land, born within a few years and a hundred miles or so of each other, who struggled against indifference, fear and bitter rivalry to be the first to cross the western ocean.  And who, by so doing, ushered in the end of the medieval age. 

http://david-boyle.co.uk/books/settingsun.html