WELL IF COLUMBUS IS RESPECTABLE AGAIN: The Portuguese Columbus: Secret Agent of King John I No, it’s probably not true.  (Although there was a DNA test sometime and now I don’t remember how it turned out.)  But the thesis is fascinating for those interested in that sort of thing… or who might decide to write a book about historical conspiracies (I hear some guy called Dan Brown did pretty well out of that sort of thing) even if my parents laugh whenever the author is mentioned.