YORK, United Kingdom — The aftershocks from Britain’s vote to leave the European Union — and the rumbles over whether the post-Brexit United Kingdom should remain united — are being felt in the land of Lord Grantham, Lady Mary and Carson the butler.As British leaders negotiate the messy divorce from the European Union, some in this vast region of Northern England, the setting for the popular and nostalgic television drama “Downton Abbey,” are calling for more independence from Westminster, further complicating a challenging balancing act for Prime Minister Theresa May.
