Treaty of Lisbon

Historical eventDecember 12009

Treaty of Lisbon

The Treaty of Lisbon entered into force in the European Union.

Everything on December 1Original source

In context

When
Tuesday, December 1 200917 years ago
Category
Historical eventA dated happening — a battle, treaty, launch, discovery, disaster or decision — recorded on this calendar day.
Era
21st century · 2000s
Recorded from
Wikipedia “On this day” feed

At a glance

Dates: From 2009.

What happened

The Treaty of Lisbon entered into force in the European Union.

December 1 through the years

Other entries on the same calendar day, in order.

  1. 2000Vicente Fox
  2. 2001United Russia
  3. 2005Perm Oblast
  4. 2006Same-sex marriage in South Africa
  5. 2009Treaty of Lisbon
  6. 2011Almaty Metro
  7. 2018Oulu child sexual exploitation scandal
  8. 2019Arsenal Women 11–1 Bristol City Women
  9. 2019Vivianne Miedema
  10. 2019COVID-19 pandemic
  11. 2020Arecibo Telescope

Also in 2009

  • May 11IraqAn American soldier in Iraq opens fire on a counseling center at Camp Liberty in Baghdad, killing five other US soldiers and wounding three.
  • May 11Space Shuttle AtlantisSpace Shuttle Atlantis is launched on the final mission to service the Hubble Space Telescope.
  • September 9Dubai MetroThe Dubai Metro, the first urban train network in the Arabian Peninsula, is ceremonially inaugurated.
  • September 18CBS StudiosAfter 72 years on radio and television, CBS Television broadcasts the final episode of Guiding Light, the longest-running soap opera in A…
  • November 17University of East AngliaAdministrators at the University of East Anglia's Climatic Research Unit discovered that their servers had been hacked, and thousands of…
  • May 252009 North Korean nuclear testNorth Korea conducted a nuclear test and several other missile tests that were widely condemned internationally and led to sanctions from…
  • May 25North KoreaNorth Korea allegedly tests its second nuclear device, after which Pyongyang also conducts several missile tests, building tensions in th…
  • August 10HandlováTwenty people are killed in Handlová, Trenčín Region, in the deadliest mining disaster in Slovakia's history.

Everything we record for 2009 →

Sources

Cite this page

“Treaty of Lisbon”, What's On This Date, https://whatsonthisdate.com/app/event/treaty-of-lisbon-2009-december-1, accessed October 27, 2026.

Cite the underlying source as well — the source links above go to the record this entry is adapted from.

Questions about this entry

When did Treaty of Lisbon happen?

December 1 2009 — 17 years ago, on a Tuesday.

Where does this text come from?

Wikipedia “On this day” feed. Summaries are short adaptations that link back to the source, not reprints.

How do I cite this page?

Use the ready-made citation near the sources at the bottom of the page, and follow the source link to cite the underlying record as well.

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