British Mandate era

Until 1923, after borders were renegotiated between the British and French governments (who controlled the northern and southern parts of the Levant, respectively, at the time), al-Mansura was a part of Lebanon. Afterward it became part of the Mandatory Palestine and was described as a hamlet by the Palestine Index Gazetteer.^[5]

In the 1931 census of Palestine, conducted by the British Mandate government, it was counted under the much larger Christian village of Fassuta. The total population of the two places were 688 inhabitants; 81 Muslims and 607 Christians, in a total of 129 houses.^[8] The houses of al-Mansura were spaciously separated from each other and the village had a church dedicated to Mari Yohanna (John the Baptist). The chief source of income was from agriculture and husbandry and the main sources of drinking water came from a well to the north and three water tanks.^[5]

In the 1945 statistics, its land was grouped with the lands of Fassuta (existent) and Dayr al-Qassi; the total population was 2,300^[3] and their total land area was 34,011 dunums.^[4] 1,607 dunams were plantations and irrigable land, 6,475 used for cereals,^[9] while 247 dunams were built-up (urban) land.^[10]

Israeli period

Al-Mansura was believed to have been attacked during the Israeli offensive Operation Hiram in October 1948. In mid-November, the Israeli Army had Palestinian Arab villages on the Lebanese border cleared, including al-Mansura. Its residents were expelled from the village, with some leaving for Lebanon while most were sent to the Arab town of Rameh in the heart of the Galilee. The Maronite Church requested that the Israeli government allow al-Mansura's inhabitants to resettle the village but were refused. The residents of al-Mansura continued to demand permission from the Israeli courts to resettle for some time after, but were unsuccessful.^[5]

Several Jewish localities have been built on al-Mansura's lands, including Elkosh established in 1949, the military base Biranit in the early 1950s, Netu'a in 1966, Mattat in 1979 and Abirim in 1980. According to Palestinian historian Walid Khalidi whose researchers visited the village before 1992, "The village houses have been completely leveled. Much of the resulting debris has been pushed together in heaps along the northern edge of the site." The only structure remaining was the partially collapsed church.^[5]