Before the Common Era

Archaeological work in Yama brought to light settlement remains ranging from the Pre-Pottery Neolithic B (PPNB) to the Ottoman period.^[3] At Ibtan, potsherds dating from the Hellenistic, Roman and Byzantine period have been found.^[4]

Middle Bronze Age II findings from Yama have been tentatively identified to belong to the ancient site of Yaham.^[3] Yaham was mentioned in Egyptian sources regarding pharaohs Thutmose III and Shoshenq I.^[5] The 15th century BCE annals describing the campaign of Thutmose III against a coalition of Canaanite city-states recount how the pharaoh camped at Yaham before marching on through the pass of Aruna (today's Wadi Ara), at whose exit he attacked and captured the city of Megiddo.^[5]

Mamluk Sultanate and Ottoman Empire

In 1265, two of the villages were mentioned among the estates which the Mamluk sultan Baibars granted his emirs after he had defeated the Crusaders: The whole of Ibthan (Bathan) was given to his emir 'Alam al-Din Sanjar al-Halabi al-Salihi,^[6] while Yamma was divided equally between the emirs Saif al-Din Itamish al-Sa'di and Shams al-Din Aqsunqur.^[7]

Yama and Ibtan appeared in Ottoman tax registers compiled in 1596, in the Nahiyas of Qaqun and Jabal Sami, respectively, of the Nablus Liwa. Yama had a population of 18 Muslim households and 5 bachelors, while Ibtan was indicated as empty even though it paid taxes.^[8]

In 1882, in the PEF's Survey of Western Palestine, only Khurbet Ibthan was noted, with "traces of ruins and a well."^[9]

British Mandate and Israel

In the 1922 census of Palestine conducted by the British Mandate authorities, Bir al-Sikka had a population of 36, Ibthan 56 and Yamma 48, all Muslims.^[10] Until 1948, all four villages were administratively related to the modern-day Palestinian town of Deir al-Ghusun.^[11][12]

Zemer's population at the end of 2009 was 5,700,^[13] and its jurisdiction is 8,203 dunams.^[14] The population increased to 6,375 in 2014.^[15] The mayor of Zemer is Yassin Harzalla.^[16]