Belgium, France, West Germany, Luxembourg, and the Netherlands signed the Schengen Agreement in Schengen, Luxembourg. It set the goal of gradually removing checks at their shared internal borders and improving cooperation to manage a common external border. This created a new model for freer travel tied to shared security rules.
The five original countries signed the Schengen Implementing Convention to turn the 1985 political agreement into workable rules. It laid out practical steps such as common visa approaches, cross-border police cooperation, and shared procedures for border management. This convention provided the legal and technical foundation needed before border checks could be removed in practice.
Italy joined the Schengen Convention, signaling that Schengen cooperation was expanding beyond the original five. Accession meant accepting the shared rules, even though full removal of border checks depended on later readiness evaluations. This step began a wider Mediterranean expansion of border-free travel.
Spain and Portugal acceded to the Schengen Convention, extending the project to the Iberian Peninsula. This required the countries to align with Schengen rules on external borders and visas, not just internal travel. Their accession helped prepare for Schengen’s first real-world start with border checks removed.
Checks at internal borders were abolished among the initial group, marking Schengen’s practical launch as a border-free travel area. The change made travel and cross-border work easier, while shifting attention to stronger shared controls at the external border. It also increased the need for shared information and police cooperation to replace routine internal border checks.
EU member states signed the Treaty of Amsterdam, which included plans to bring Schengen rules into the EU’s legal system. This mattered because Schengen began as a separate intergovernmental agreement, and legal integration aimed to make governance more consistent across the EU. The treaty set the stage for Schengen to become part of EU law when it entered into force later.
Austria began full participation in the border-free area when internal border checks with other Schengen states were abolished. This was an important expansion toward Central Europe and increased the length of the Schengen external border. Austria’s entry also showed how non-original members had to meet operational requirements before border checks could end.
When the Treaty of Amsterdam entered into force, the “Schengen acquis” (the full set of Schengen rules) was integrated into the EU legal framework. This shifted Schengen from a separate treaty system into a core EU policy area, supporting more unified decision-making and implementation. It also helped align enlargement and oversight with EU institutions.
Denmark, Finland, Sweden, Iceland, and Norway became full members of Schengen cooperation, ending internal border checks within that group and with other Schengen states. This expansion was significant because it brought in non-EU countries (Iceland and Norway) through association agreements. It also showed that Schengen could grow beyond EU membership when countries adopted the common rules.
The EU adopted the Schengen Borders Code to standardize how external borders are managed and how internal borders should function without routine checks. The code aimed to make rules clearer and more uniform across participating countries. This legal framework supported both security and predictability as Schengen continued to expand.
Nine EU countries (Czech Republic, Estonia, Hungary, Latvia, Lithuania, Malta, Poland, Slovakia, and Slovenia) joined the Schengen area, with internal land and sea border checks abolished. This was the biggest single enlargement and extended border-free travel deep into Central and Eastern Europe. The change also shifted EU external border responsibilities eastward, requiring upgraded border systems and coordination.
Internal air border checks were lifted for the nine countries that joined in December 2007, completing that expansion. Airports adjusted operations to separate Schengen and non-Schengen passengers, making travel within the enlarged area closer to domestic travel. This final step reduced routine passport controls for many flights inside Europe.
Liechtenstein joined Schengen, removing routine passport controls at its border with Switzerland and other Schengen countries. This small but important expansion showed that even microstates could participate when they met the operational requirements. It also further connected the Schengen travel area across the Alpine region.
The second-generation Schengen Information System (SIS II) went live, upgrading the main shared database used for border, security, and law enforcement cooperation. SIS II improved capabilities such as handling more data and supporting modern identification tools (for example, biometrics like fingerprints). This modernization strengthened the “compensatory measures” that help Schengen function without routine internal border checks.
Schengen Area: Creation and Expansion (1985-2013)