Would I be legally able to live and work in the country of my choice, as long as I wasn't a member of a particularly unpopular religion/group? Would I have any paperwork to file? If I just showed up in a ship off the English coast, would anyone be there to 'process' me? Would it make any difference if I wanted to move to a non-Christian country like Istanbul or Cairo? I'd love to know the answer!

More general background interest here: with all the debates about immigration controls in Europe and the United States over the last couple of years, I'd be very grateful for some historical perspective on the question of when and how general purpose immigration restrictions came into place in Europe. I'm somewhat aware of specific restrictions on immigration by particular groups (Jewish people, people from China) in the US and Europe at various points, but I don't know of any wide-reaching systematic policies.