
Arab–Byzantine wars
Arab–Byzantine wars: The city of Syracuse was captured by the Aghlabids (pictured) as part of the Muslim conquest of Sicily.
In context
- When
- Wednesday, May 21 8781148 years ago
- Category
- Historical eventA dated happening — a battle, treaty, launch, discovery, disaster or decision — recorded on this calendar day.
- Era
- 9th century · 870s
- 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: 629 – 1050.
Place: Levant, Italy.
Type: series of wars.
Key figures / parties: Byzantine Empire, Ghassanids, Mardaites, Medieval Armenia, First Bulgarian Empire, Kingdom of Italy, Italian city-state, and Rashidun Caliphate.
What came before
Part of: Muslim conquests.
Background See also: Roman–Persian Wars , Byzantine–Sasanian wars , Byzantine–Sasanian War of 602–628 , and Siege of Constantinople (626) The prolonged and escalating Byzantine–Sasanian wars of the 6th and 7th centuries and the recurring outbreaks of bubonic plague ( Plague of Justinian ) left both empires exhausted and vulnerable in the face of the sudden emergence and expansion of the Arabs .
What happened
History Arab conquests, 629–718 Territorial extent of the Arab conquests :    Expansion under Muhammad , 622–632    Expansion during the Rashidun Caliphate , 632–661    Expansion during the Umayyad Caliphate , 661–750 According to Muslim biographies, Muhammad, having received intelligence that Byzantine forces were concentrating in northern Arabia with intentions of invading Arabia, led a Muslim army north to Tabuk in present-day northwestern Saudi Arabia ,
The Arab–Byzantine wars or Muslim–Byzantine wars were a series of wars from the 7th to 11th centuries between the successive Islamic caliphates and the Byzantine Empire. Following the Byzantine defeat at the Battle of the Yarmuk, Muslim armies conquered most Byzantine territory in the Levant, Egypt and North Africa within decades. Arab expansion subsequently slowed to a more gradual rate, following two failed sieges of the Byzantine capital of Constantinople in the late 7th and early 8th centuries.
May 21 through the years
Other entries on the same calendar day, in order.
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Sources
- Wikipedia article (text, CC BY-SA 4.0)
- Licence: CC BY-SA 4.0 for adapted text · how we source this
Cite this page
“Arab–Byzantine wars”, What's On This Date, https://whatsonthisdate.com/app/event/arab-byzantine-wars-878-may-21, accessed October 26, 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 Arab–Byzantine wars happen?
May 21 878 — 1148 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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