Today, on November 9, Azerbaijan marks National Flag Day.

The Azerbaijani Democratic Republic (ADR), which existed until 1920, adopted Azerbaijani tricolor as the national flag of Azerbaijan Democratic Republic on November 9, 1918.

After the Bolshevik occupation on April 27, 1920, the flag of the Azerbaijani Democratic Republic was replaced with the USSR’s red flag with hammer and sickle.

On November 17, 1990, the flag of the Azerbaijani Democratic Republic was restored under the decision of the Supreme Majlis of the Nakhchivan Autonomous Republic and adopted as the national flag of the autonomous republic.

After gaining independence in 1991, the Supreme Council of the Azerbaijan Republic announced a tricolor flag with a star and a crescent as the national flag of Azerbaijan on February 5, 1991.

On November 18, 2009, Azerbaijani President Ilham Aliyev signed an order to declare November 9 as National Flag Day.

National Flag Square was also inaugurated with President Ilham Aliyev's participation in Baku on September 1, 2010.

The national flag with a 162 meter-high flagpole measures 70 meters high and 35 meters wide and weighs 350 kilograms. The total weight of the construction is 220 tons. The flag's total area is 2,450 square meters with a weight of about 350 kilograms.

The author of the formula “Turkic freedom, modernity and Islamic culture”, which was the major principle of the national independence ideology early in the 20th century, was the great Azerbaijani thinker Alibey Huseynzade.

The national flag of Azerbaijan consists of three horizontal equal strips. The upper strip is of blue color, the middle-of red, the lower is green. In the center of the flag, on the red strip, there is an eight-pointed star and crescent; both are white.

The basic description of the flag, along with the ratio, can be found in Article 23.II of the Constitution of Azerbaijan that was adopted on November 12, 1995. State flag of the Azerbaijani Republic consists of three horizontal stripes of same width. Upper stripe is blue, middle stripe is red, and the lower one is green; in the middle of red stripe on both sides of the flag white crescent with eight-pointed star are depicted. Width of the flag constitutes half of its length.

Further specifications of the national flag were set out in the Presidential Decree "On the National Flag of the Republic of Azerbaijan" issued on February 5, 1991. The ratio was kept at 1:2, which was used in the Soviet era. Each stripe is 1/3rd of the total height of the flag and extends to the full length of the flag. The star and crescent was placed in a box that has a ratio of 3:4; the crescent is shifted 1/60th from the center of the flag. At the outside diameter of both the crescent and the red inside circle, it will intersect with the diameter of the white eight-pointed star. The diameter of the star is 1/6th of the height of the flag; the inscribed circle in this star is 1/12th of the height of the flag. The flag is also described in the technical specification "AZS 001-2006.