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On June 17, 1972, five men were arrested while trying to plant microphones at the Democratic Party headquarters in the Watergate building in Washington D.C. Investigation revealed the operation had been ordered by members of President Nixon's re-election campaign. The Watergate scandal led Nixon to become the only American president to resign, on August 9, 1974.

On June 17, 1992, world leaders signed the United Nations Framework Convention on Climate Change (UNFCCC) in Rio de Janeiro during the Earth Summit. The convention laid the foundations for future international climate agreements, including the Kyoto Protocol (1997) and the Paris Agreement (2015). The Convention on Biological Diversity and the Convention to Combat Desertification were also signed.

On June 17, 2022, the European Commission formally recommended granting Ukraine and Moldova the status of candidates for accession to the European Union, a week after their presidents and the President of Georgia visited Kyiv in a show of support. Ukraine's candidacy, submitted days after the Russian invasion, was approved by the European Council on June 23 — one of the most important geopolitical decisions in recent EU history.