Muslims (Persian, Turkic groups and Kurds) formed an absolute majority in Iranian Armenia, comprising some 80% of the population, whereas Christian Armenians formed some 20% of the population. According to the "Kameral'noe Opisanie", the settled and semi-settled Muslim population numbered more than 74,000. However, there are flaws regarding this number, as it doesn't account for the settled and semi-settled Muslims that left immediately after the Iranian defeat. For example, basically the entire Persian ruling elite and the military officer apparatus, "most of whom resided in the administrative centers", migrated to mainland Iran after the defeat. Furthermore, a number of the Turkic and Persian soldiers had perished in the 1826–1828 war, which lead to the Russian conquest of the Erivan and Nakchivan Khanates. According to estimations, some 20,000 Muslims had left Iranian Armenia or were killed during the 1826–1828 war. According to professor of history George Bournoutian, it can therefore be taken for granted that the combined Persian and Turkic (settled and semi-settled) population of Iranian Armenia amounted some 93,000, instead of 74,000.