Romania and Bulgaria joined the European Union.
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The European Union's climate service declared that 2023 was the hottest year on record.
The European Union is established as the Maastricht Treaty is signed.
Bill Gates had a pie thrown in his face while visiting EU officials in Brussels, Belgium.
The European Union expanded the 1951 Stresa Convention.
The UK's prime minister Boris Johnson compared himself to The Hulk in his efforts to steer the country out of the European Union.