The Battle of Ajnadayn (Arabic: معركة أجنادين‎), fought on July 30, 634, in an unknown location close to Beit Guvrin in present day Israel; it was the first major pitched battle between the Byzantine (Roman) Empire and the army of the Arabic Rashidun Caliphate. The result of the battle was a decisive Muslim victory. The details of this battle are mostly known through Muslim sources, such as 9th century historian Al-Waqidi.

• http://en.wikipedia.org/wiki/Ajnadayn