The majority of Kurds in Syria originally came from Turkey in the 1920s. Kurdish immigration waves to Syria's Jazira province started immediately after WWI. After the war, the construction of road networks and the railway extension to Nusaybin have intensified the Kurdish immigration from the Anatolian mountains to Syrian Jazirah. After that, massive waves of Kurds fled their homes in the mountains of Turkey after the failed Kurdish rebellions in Kemalist Turkey. It is estimated that 25,000 Kurds fled at this time to Syria, under French Mandate authorities, who encouraged their immigration, and granted them Syrian citizenship. The French official reports show the existence of at most 45 Kurdish villages in Jazira prior to 1927. In 1927, Hadjo Agha, the chief of the powerful Kurdish tribe Havergan, arrived with more than 600 families in Qubour el-Bid (later renamed al-Qahtaniyah). The mandatory authorities continued to encourage Kurdish immigration into Syria, and a new significant wave of refugees arrived in 1929. The number of Kurds settled in the Jazira province during the 1920's was estimated between 20,000 and 25,000. With the continuous intensive immigration the villages numbered between 700 and 800 in 1939. Consequently, Kurds became majority in the districts of Tigris (later renamed al-Malikiyah) and Qamishli, while Arabs remained the majority in Hasakah district.