Multiple Choice, Single Answer

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The modern passport emerged gradually rather than through a single decisive invention. Early forms of travel documents, often little more than letters of safe conduct issued by monarchs, served to protect the bearer rather than to verify identity in the way passports do today. It was only after the disruptions of the First World War, when governments sought tighter control over who crossed their borders, that standardized booklets bearing photographs and physical descriptions became widespread. A 1920 international conference helped establish common formats among participating nations, though full uniformity took decades longer to achieve. Notably, before this period, many travelers crossed borders across Europe with minimal documentation, a freedom of movement that later generations would find difficult to imagine.