Establishment
The Nordic Passport Union was established in three steps. The first step came in 1952, in the form of agreements by the Nordic countries to abolish passports for travel between them and to readmit aliens having entered illegally into one Nordic country from another. The second step was implemented in 1954, when the agreement was extended to allow citizens to reside and work in any Nordic country without a residence or work permit. The third step was the removal of passport checks for aliens at internal Nordic borders by a treaty signed on 12 July 1957 and coming into force on 1 May 1958.
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