Also, in Caxtons time the powers that be made up Engish GRAMMER rules by using many of the rules of Latin - the language of the educated back then. That's why split infinitives and dangling participles are no-nos, even though they are used by us common folk all the time.
So we are actually speaking a Germanic derived creole, and trying to conform to rules of a classical language which has not been spoken for centuries.

Mark