As a result of discriminatory policy pursued by Soviet Russia against aboriginal Muslim-Turk population of the South Caucasus, as well as, deportations and massacres over the period from Gulistan (1813) and Turkmenchay (1828) agreements to the time of establishment of Azerbaijan Democratic Republic, ethnic composition, number and location of Azerbaijani people were changed deliberately, the number of Azerbaijanis living there was considerably decreased. Mass resettlement of Armenians from different countries to the North Azerbaijani lands after the Russian occupation, exerted strong impact on ethno-political situation and Azerbaijanis were deported from their ancestral lands. With considerable assistance and support of the tsarist government, the Armenians had repeatedly committed massacres against Azerbaijanis. At the same time, the information about Azerbaijanis was deliberately distorted in demographic statistical sources of that period. Despite all this, the Azerbaijanis still remained to be the major ethnic factor in the Caucasus as it was in previous historical periods, in the late19th and early 20th centuries, also in the time of Azerbaijan Democratic Republic. In November, 1918, it was noted in special memorandum presented by Alimardan bey Topchubashov to representatives of the Entente countries in Istanbul that 7667370 people lived in 237055 sq. km. territory of the South Caucasus. Ethnic composition of them was as follows: 3306000 (43, 1%) Muslims, 1786000 (23, 3%) Armenians, 1641000 (21, 4%) Georgians. According to that document, 2353000 people lived in the territory of Azerbaijan Democratic Republic which was equal to 30.7 percent of population of the South Caucasus. The documents submitted by the Government of the Azerbaijan Democratic Republic to the Paris Peace Conference, stated that, the territory under the actual authority of   the Azerbaijan Democratic Republic covered 38 percent, but together with the areas where Azerbaijani authority was spread over, it covered 60. 7 percent of territory of the South Caucasus. According to the documents submitted to the Paris Peace Conference, the population of the South Caucasus was in general 8081668 people. 4617671 (57.1%) of them lived in Azerbaijan. The composition of population was as follows: 75.4% (3481889 people) Azerbaijanis, 17.2% (795312 people) Armenians, 0.6% (26585 people) Georgians, 6.7% (310885 people) other nationalities. The Government of the Azerbaijan Democratic Republic paid special attention to definition of number and ethnic composition of population of the country. The address-calendar of 1920 of the Azerbaijan Democratic Republic also provides information on population in table. As that table was compiled on the basis of the calendar for the Caucasus for the year 1917, in fact, reflects the status of the year 1916. On the other hand, that table did not give the exact number of turkish-muslim population as well. Thus, the table below indicates the number of population living in indisputable territory of the Azerbaijan Democratic Republic.

Population of the Azerbaijan Democratic Republic
(Compiled on the basis of “Caucasus calendar” edition of the year 1917)

At that time the total number of population was 2861862, i.e. 29.4 persons per sq. km. in indisputable territory of the Azerbaijan Republic (97.3 thousand square kilometres). Ethnic composition of population was as follows: Muslims (mainly Azerbaijani Turks) 62.8%, Armenians 21,4%, Georgians 0,6%, Russians 7,5%, other nationalities 2,3%. According to above mentioned numbers, the total population in all territory of the Azerbaijan Democratic Republic (113.9 thousand sq. km) was recorded at more than 3.3 million people in 1916. Azerbaijani people faced demographic collapses and decreased in number as a result of mass genocides and ethnic cleansing carried out by Armenians also over the period after 1916.  Calculations show that, the population of the Azerbaijan Democratic Republic decreased to 2.6 million people on the eve of invasion in April, 1920. On the other hand, according to the official data, the population of Azerbaijan Soviet Socialist Republic (86.6 thousand sq. km) was recorded at 1952000 people. In consideration of this fact, approximately 2189250 people lived in indisputable area of the former Azerbaijan Democratic Republic. If this figure is compared with the one at the beginning of the year 1916, it becomes clear that, the population living in indisputable territory of the Azerbaijan Democratic Republic decreased to 700 thousand people on the eve of its fall. These were the painful results of the genocides committed against the Azerbaijani people during the First World War (1914-1918).