The first of five clues. Each one below gives a little more away.
I am a request rather than a right. I ask other countries to let you through.
For most of the nineteenth century, most of the world did not need me at all.
A war made me permanent, and I was supposed to be temporary.
My photograph only became compulsory in the 1910s.
The little book you hand over at the border.
Passport
The modern passport is a 1914 wartime measure that was never repealed. Before it, crossing most European borders required no document whatsoever.
A passport does not grant you the right to enter anywhere. It is a request from your own government that another government let you pass, which is why the first page is usually addressed to whoever is reading it. Through most of the nineteenth century Europe abandoned them as a relic; you could cross most of the continent with nothing at all. The First World War brought them back as a security measure meant to last for the duration, the photograph was added at the same time, and the emergency arrangement quietly became the permanent architecture of borders.
Reading five clues at once is not the game. In the real thing they arrive one at a time and every wrong guess costs an hour. Play mystery #45 · today's mystery · the vault
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