Nathan Perl-Rosenthal immerses us in sailors’ pursuit of safe passage through the ocean world during the turbulent age of revolution. Challenged by British press-gangs and French privateersmen, who considered them Britons and rejected their citizenship claims, American seamen demanded that the U.S. government take action to protect them. In response, federal leaders created a system of national identification documents for sailors and issued them to tens of thousands of mariners of all races―nearly a century before such credentials came into wider use.