Before the colonization of the Spanish Empire, flags were not common in the Americas, as there were no political entities that united the indigenous peoples and no records. Research shows that Mapuche troops seem to have used a flag with a white star on a blue background, vaguely similar to the modern flag of Chile, as well as a flag with a white eight-pointed star in the center of a blue stepped cross or a star with a white border on a red background. Spanish troops used several flags, such as the Burgundy Cross, a red cross on a white background that was raised on ships of the Spanish fleet and used in colonial territories. In 1785, a unified flag for the Spanish navy was created based on the modern Spanish flag, but the Cross of Burgundy continued to be used.

In 1810, the First National Government Junta was formed in Chile, which became the first form of autonomous government for the country and began the process of Chilean independence. The junta declared itself loyal to King Fernando VII, while retaining the symbols of Spanish rule. During the reign of Jose Miguel Carrera, the desire for independence intensified, and he introduced national symbols, including a cockade, coat of arms, and a special flag. The first flag was embroidered by the ruler's sister and first raised in El Monte on July 4, 1812, in honor of US Independence Day. The flag consisted of three stripes - blue, white, and yellow - symbolizing the three powers of the state: national greatness, law, and strength.
The Chilean War of Independence, which lasted from 1810 to 1818, played an important role in the struggle for the country's independence from Spain. During this period, symbols were adopted that reflected the patriotic ideals of the population. One of the most important symbols is the tricolor flag, also known as the Patria Vieja.

The blue-white-yellow version of the flag is the most popular and is used during official celebrations. However, there are other versions with different color combinations, such as white, blue and yellow. In some cases, the red cross of Santiago, which has Spanish roots and symbolizes the country's pride, may be added to the flag alongside the coat of arms.
The triumph of the patriots in the Battle of Chacabuco led to the period of the "New Fatherland". The new national flag, known as the "flag of transition," was first adopted in 1817. It consisted of blue, white, and red stripes. The colors were taken from Ersilla's description, where they symbolized the distinction of Mapuche military units. These colors corresponded to the colors of the flag of the Fatherland, with red instead of yellow, which symbolized the blood shed during the fighting. However, this flag did not receive official status and disappeared in a few months. The last time the flag was raised was during a ceremony in Rancagua, shortly before the adoption of the current national emblem. There is information about a possible temporary flag that could have changed the order of the stripes and contained a white star on the central stripe, but this is not confirmed by most Chilean historians.

The concept of the modern Chilean flag was developed by José Ignacio Zenteno, and the design itself belongs to Antonio Arcos, a Spanish-Chilean military officer. The flag was officially approved on October 18, 1818. The star on the flag is not located vertically in the center of the canton, but is slightly inclined to the pole, which causes its sides to be projected onto the golden section. This star reflects the image of the morning star, or the planet Venus, which is depicted as an octagonal star and symbolizes the combination of European and indigenous traditions. In the center of the flag was the coat of arms adopted in 1817. There was a flag that used the full version of the state coat of arms and was used until 1834. After some time, due to the complexity of making such a flag, it had to be simplified by removing the coat of arms and the star. However, this ban applied only to the population, and the government and army continued to use the full flag. But this change did not please the population, which felt deprived of national symbols, so in July 1852 a new decree allowed the use of the flag with a star.