Jund Filastin (Arabic: جند فلسطين, "the military district of Palestine") was one of several districts of the Ummayad and Abbasid Caliphate province of Bilad al-Sham (Syria), organized soon after the Muslim conquest of Syria in the mid 7th-century. According to al-Biladhuri, the main towns of the district, following its conquest by the Rashidun Caliphate, were Gaza, Sebastiya, Nablus, Caesarea, Ludd, Yibna, Imwas, Jaffa, Rafah, and Bayt Jibrin. At first, under the early Umayyad caliphs, Ludd served as the district capital. After the caliph Suleiman ibn Abd al-Malik founded the nearby city of Ramla, he designated it the capital, and most of Ludd's inhabitants were forced to settle there. In the 9th-century, during Abbasid rule, Jund Filastin was the most fertile of Syria's districts, and contained at least twenty mosques, despite its small size.
The Arab tribes that settled Jund Filastin after the Muslim conquest were the Lakhm, Kindah, Qais, Amilah, Judham and the Kinanah; at the time of the Arab conquest, the region had been inhabited mainly by Aramaic-speaking Monophysite Christian peasants. The population of the region did not become predominantly Muslim and Arab in identity until several centuries after the conquest. At its greatest extent, Jund Filastin extended from Rafah in the south to Lajjun in the north, and from the Mediterranean coast well to the east of the southern part of the Jordan River. The mountains of Edom, and the town of Zoar at the southeastern end of the Dead Sea were included in the district. However, the Galilee was excluded, being part of Jund al-Urdunn in the north.
After the Fatimids conquered the district from the Abbasids, Jerusalem eventually became the capital, and the principal towns were Ashkelon, Ramla, Gaza, Arsuf, Caesarea, Jaffa, Jericho, Nablus, Bayt Jibrin, and Amman. The district persisted in some form until the Seljuk invasions and the Crusades of the late 11th-century.