Romania and Bulgaria joined the European Union.
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The dwarf planet Ceres was discovered by an Italian monk called Giuseppe Piazzi.
Portuguese navigators discovered Rio de Janeiro.
The country of Czechoslovakia peacefully dissolved into two nations, the Czech Republic and Slovakia.
The Union Jack flag was flown for the first time in Dublin, Ireland, to commemorate the union between Great Britain and Ireland.
The Euro currency was introduced and adopted by 11 Member States.
