Historical eventMay 141264

Second Barons' War

Second Barons' War: King Henry III was defeated at the Battle of Lewes and forced to sign the Mise of Lewes, making Simon de Montfort the de facto ruler of England.

Everything on May 14Original source

In context

When
Wednesday, May 14 1264762 years ago
Category
Historical eventA dated happening — a battle, treaty, launch, discovery, disaster or decision — recorded on this calendar day.
Era
13th century · 1260s
Calendar
Julian — as recorded at the time
Recorded from
Wikipedia “On this day” feed

Dates before 15 October 1582 are in the Julian calendar, so the weekday shown follows the Julian reckoning of the time.

At a glance

Dates: From 1264.

What happened

Second Barons' War: King Henry III was defeated at the Battle of Lewes and forced to sign the Mise of Lewes, making Simon de Montfort the de facto ruler of England.

May 14 through the years

Other entries on the same calendar day, in order.

  1. 1264Second Barons' War
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  3. 2004Frederik X
  4. 2004Constitutional Court of Korea
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  7. 2010Space Shuttle Atlantis
  8. 2010Stephen Timms
  9. 2012Agni Air Flight CHT
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  11. 20222022 Buffalo shooting

Also in 1264

  • August 14War of Saint SabasWar of Saint Sabas: A Genoese fleet captured or sank most of the ships of a Venetian trade convoy off the Albanian coast.
  • August 8ReconquistaReconquista: In the early stages of the Mudéjar revolt, Muslim rebels captured the Alcázar of Jerez de la Frontera in present-day Spain,…
  • January 23Louis IX of FranceKing Louis IX of France issued the Mise of Amiens, a settlement between King Henry III of England and barons led by Simon de Montfort hea…

Everything we record for 1264 →

Sources

Cite this page

“Second Barons' War”, What's On This Date, https://whatsonthisdate.com/app/event/second-barons-war-1264-may-14, accessed October 24, 2026.

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Questions about this entry

When did Second Barons' War happen?

May 14 1264 — 762 years ago, on a Wednesday.

Is this a Julian or a Gregorian date?

It is the date as recorded at the time, on the Julian calendar. The Gregorian equivalent falls about ten days later; sources from different countries may give either.

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?

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