The Czech Republic’s flag—two horizontal bands of white (top) and red with a blue triangle at the hoist—derives from Czechoslovakia’s 1920 design. The white and red reflect Bohemian heraldry; blue evokes Moravia and the pan‑Slavic palette. After 1992’s dissolution, the Czech Republic retained the flag, with law fixing a 2:3 ratio, colour shades, and vertical display (triangle upper left). Protocol prescribes official use on state buildings, holidays, and diplomatic occasions, forbidding desecration and improper handling.
The national flag of the Czech Republic is a direct heir to the 1920 flag of Czechoslovakia, a design crafted to balance historic heraldry with modern distinctiveness. When Czechoslovakia formed in 1918 from lands of the defunct Austro‑Hungarian Empire, the provisional flag employed Bohemia’s longstanding colours—white and red—in two horizontal bands. This, however, proved too similar to the Polish flag and insufficient to represent the state’s multi‑regional character. In 1920, legislators added a blue triangle at the hoist, creating a tricolour in pan‑Slavic hues while preserving the familiar white‑over‑red arrangement.
White and red come from the coat of arms of the Kingdom of Bohemia, which depicts a silver (white) double‑tailed lion on a red field. Blue has been linked to Moravia’s heraldry and to broader Slavic symbolism. The resulting flag paired historical resonance with sea‑to‑shore readability, its hoist‑side wedge distinguishing it from the many horizontal tricolours of Europe. The proportions were set at 2:3, with the triangle extending to the midpoint of the flag’s length.
The interwar republic flew the flag domestically and abroad until 1938–39, when German occupation dismantled the state. The Czech government‑in‑exile continued to use the tricolour as a symbol of legitimate sovereignty. After World War II, the re‑established Czechoslovakia restored the flag. Under communist rule (1948–1989), the design remained unchanged even as the state’s arms and other insignia evolved along ideological lines.
As Czechoslovakia prepared to dissolve peacefully in 1992, negotiators agreed that the Czech Republic could retain the 1920 flag, while Slovakia adopted a distinct tricolour with national arms. Czech law now codifies precise colour shades, the 2:3 ratio, and methods of vertical display (the blue triangle upper left). The flag must be treated with dignity; statutes prohibit desecration and set penalties for misuse. Public institutions fly it on state holidays and at diplomatic posts with established order‑of‑precedence rules when displayed with other flags, including the European Union flag.
The continuity of the Czech flag over a century—through democracy, occupation, socialism, and democratic restoration—has made it a widely recognised emblem of national resilience. Its geometry reads clearly on façades and masts, and its colours carry layered meaning: medieval heraldry, Slavic fraternity, and a modern constitutional identity.