Terezín consists of four municipal parts (in brackets population according to the 2021 census):[2] The fortress town was named after Empress Maria Theresa (Czech: Marie Terezie).

On 10 January 1780, Habsburg Emperor Joseph II ordered the erection of the fortress, named Theresienstadt after his mother Empress Maria Theresa.

In the times of Austria–Prussia rivalry, it was meant to secure the bridges across the Ohře and Elbe rivers against Prussian troops invading the Bohemian lands from neighbouring Saxony.

Garrison church in the Main Fortress was designed by Heinrich Hatzinger, Julius D'Andreis and Franz Joseph Fohmann.

During the Austro-Prussian War, on 28 July 1866, part of the garrison attacked and destroyed an important railway bridge near Neratovice (rail line Turnov–Kralupy nad Vltavou) that was shortly before repaired by the Prussians.

[6] This attack occurred two days after Austria and Prussia had agreed to make peace, but the Theresienstadt garrison was ignorant of the news.

These were primarily Czechs, later other nationals, for instance citizens of the former Soviet Union, Poles, Germans, and Yugoslavs.

Most of the prisoners were arrested for various acts of resistance to the Nazi regime; among them were the family members and supporters of the assassins of Reinhard Heydrich.

By 1940, Germany assigned the Gestapo to adapt Terezín, better known by the German name Theresienstadt, as a ghetto and concentration camp.

[8] Part of the fortification (Small Fortress) served as the largest Gestapo prison in the Protectorate of Bohemia and Moravia.

[8] The complex was taken over for operation by the International Red Cross on 2 May 1945, with the Commander and SS guards fleeing within the next two days.

At least 548 people died in the camp during the years 1945–1948 due to poor living conditions, malnutrition and infectious diseases, but also as a result of the violence of the guards.

[12] According to the Fund, a long-term conservation plan was conceived, which includes further repairs, documentation, and archaeological research.

The organization called for a comprehensive conservation plan, while providing funding for emergency repairs from American Express.