In today's world of constant identification checks, it's difficult to recall that there was ever a time when "proof of identity" was not a part of everyday life. And as anyone knows who has ever lost a passport, or let one expire on the eve of international travel, the passport has become an indispensable document. But how and why did this form of identification take on such a crucial role?

In the first history of the passport in the United States, Craig Robertson offers an illuminating account of how this document, above all others, came to be considered a reliable answer to the...