The flag was adopted on July 3, 1962. A similar version was used by the Algerian government in exile from 1958 to 1962.
The flag's design is derived from the standard of Emir Abdel Kadir in the 19th century which consisted of two equal vertical bands, green and white, as well as being inspired from the flag of the Algerian Regency from the 16th to the 19th century, which consisted of a white crescent and star on a red background (the same as the modern flag of Turkey; the Algerian Regency was an autonomous vassal of the Ottoman Empire). However, for the most part its history is unclear. It is also believed to be based on a flag created in 1928 by Messali Hadj, a nationalist leader. White, green and red, along with the star and crescent have been used historically in Islamic countries.
Algerian ships fly the national flag as their ensign, except for ships of the Algerian National Navy, which use the national flag charged with two red crossed anchors in the canton as the naval ensign.
The Western blazon is per pale Vert and Argent; a crescent and star Gules.
Unlike many African flags, the features of the flag are set down precisely, being described as:
a green and white rectangle embossed by a red star and a red crescent ... the green must be a composition of equal yellow and blue having [with] a wavelength of 5.411 and the position 600 on the normal spectre. The red must be pure, of primary indecomposable colour, and exempt of blue and yellow having, [with] a wavelength of 6.562 and the position 285 on the normal spectre