Although paper travel documents have been around at least since Biblical times, it wasn’t until the 15th century that the form of the modern passport began to take shape. The earliest known European reference to a so-called “safe conduct” document dates to the reign of Henry V, when Parliament endorsed the King’s power to supply such documents to both British subjects and foreign nationals.
These official letters picked up their modern moniker in the 17th century, when King Louis XIV issued letters known as “passe ports,” a reference to passing through a ship’s port, or “passe portes,” describing the act of entering a city’s gates. In part, the name stuck because French was the international language of diplomacy until the early 20th century.
The first passports were typically a folded single-sheet certificate, evolving into a page folded in eight sections and bound with a cardboard cover. Though passports were gradually adopted by most developed nations during the 19th century, in times of peace the documents were viewed as barriers, rather than aids, to travel.
As railways began linking all parts of the continent, travel between European countries became much easier, and checking passports at each border crossing became a logistical nightmare. France eliminated the use of passports in 1861, with several other countries following their lead.
However, the turmoil of World War I again made passports essential for international travel, and in 1920, the League of Nations created its first international passport standards. These included recommendations that countries adopt a 32-page booklet with photographic identification and written in at least two languages, which would remain valid for no less than two years. As technology improved, passports increasingly included watermarked paper, overprinted designs, laminated photos, and machine-readable bar codes or computer chips.