The Lezghi of Azerbaijan, numbering approximately 441,000 people, are Engaged yet Unreached. They are described as a Lezgic people of the Samur River basin whose ancestors' 26 tribes united to form ancient Caucasian Albania in the 4th century BC, later absorbed into Russia by the 1813 Treaty of Gulistan, their homeland split when the Soviet Union collapsed in 1991 They are an Indigenous people, with Lezgin / Lezghi as their ethnic/kinship group and are in the Caucasus people cluster of the Eurasian Peoples. Their primary religion is Sunni Islam. They primarily speak Lezghian.