The Levant Egypt North Africa Anatolia & Constantinople Border conflicts Sicily and Southern Italy Naval warfare Byzantine reconquest Ridda Wars Conquest of Sasanian Persia Conquest of Byzantine Syria Campaigns in Africa Campaigns in Armenia and Anatolia The Battle of Fahl (Arabic: يوم فحل, romanized: Yawm Faḥl), also known as the Battle of the Marshes (Yawm al-Radagha) and the Battle of Beisan (Yawm Baysān), was a major battle in the Muslim conquest of Byzantine Syria fought by the Arab troops of the Rashidun Caliphate and Byzantine forces at or near Pella (Fahl) and nearby Scythopolis (Beisan), both in the Jordan Valley, in December 634 or January 635.

Pella was subsequently captured, while Beisan and nearby Tiberias capitulated after short sieges by detachments of Muslim troops.

800), which is the version generally followed by al-Yaqubi (d. 897), the Battle of Fahl took place on Dhu al-Qada 13 AH (December 634 or January 635 CE).

[3] The Muslims pursued them there, but were hindered on the way by muddy ground around Beisan (Scythopolis to the Byzantines),[4] a town located west of the River Jordan, 12 kilometers (7.5 mi) from Fahl.

While the city may have been captured during the Muslim victory, it also may have hosted the surviving Byzantine troops from that battle and held out, capitulating after a four-month siege.

[7] According to one of the Muslim accounts associated with the narrative of Ibn Ishaq and al-Waqidi, the Byzantines suffered huge fatalities, with one reporting the fantastical figure of 100,000 slain with survivors barricading in Fahl.

[10] After his victory, Abu Ubayda moved on to Homs (Emesa to the Byzantines) with Khalid and the main body of troops, leaving Shurahbil and Amr ibn al-As in charge of Fahl.

Meanwhile, Abu'l-A'war secured the capitulation of Tiberias on similar terms once the city surrendered after its defenders became aware of the Byzantine defeats in Damascus and Fahl.