It seems contradictory that in the era of increasing globalisation we are seeing so much nationalism and separatism doesn't it? But this is a phenomenon explained really well by Harvey (1989) if you want some extra reading! Its all about control, suddenly forces affecting a community, region or even country are outside the control of those affected by it for example trading rules set the the IMF - think about the Brexit campaign - lets take back control! The less control people feel they have the tighter they hang on or even wish to revert back, this usually includes the idea of heritage, of culture rooted in history.