Czech Flag

The Czech Republic's flag is red, white and blue. These are traditional Bohemian colors that were taken from various coats of arms.

Before the Velvet Divorce, the Czechoslovakian government passed a resolution that the new states, Czech Republic and Slovakia, could not use any emblems of the former state.

Slovak flag

Slovakia adopted a new white, blue, and red flag with its coat of arms on it.

However, the Czech Republic went ahead and maintained the former Czechoslovakian flag that had been adopted on March 30, 1920. Slovakia was upset that the ČR violated the resolution to not use any of the former emblems. The rationale used was that the country which passed the resolution no longer existed so the Czechs kept the flag. Probably just one more thing that annoyed Slovakia.