Jan, or Janin? Gossart, or Gossaert? Or Mabuse? After a mere five centuries, we haven’t settled on a name quite yet (even for this exhibition: at the Metropolitan Museum, the same show spelt it “Gossart”). We don’t know where he was born, although Maubeuge, then in Hainault, now in France, is the best guess, hence “Mabuse”. His birth date too is a mystery: the Grove Dictionary of Art suggests 1478, while the National Gallery just shrugs and gives us “active 1503”. What is in no doubt, however, in this very model of an exhibition, is that Jan Gossaert represented not merely one of the peaks of northern Renaissance art, but that, in a constantly surprising career, he also synthesised great swathes of the Italian art world, both classical and Renaissance, creating something new and hugely potent.