England is a nation divided. In one camp, nationalists decry the diabolical threat to their freedom posed by dastardly Continentals, instead throwing their hopes on a shadow empire of boundless trading opportunities. In the other, pro-Europeans bitterly protest that their country is making a cataclysmic mistake and bide their time. Sound familiar? Just kidding. It’s not Boris Johnson’s Brexit Britain but the England of the late 16th century, the subject of “In Search of a Kingdom.”