The Mexican flag has undergone several changes throughout history. The first national flag was created in 1821 and was influenced by flags used during Mexico's War of Independence, including the Standard of the Virgin of Guadalupe. The unified Army of the Three Guarantees adopted a flag with red, green, and white stripes after independence from Spain was achieved. A third official flag was introduced during the Second Mexican Empire, retaining the tricolor stripes but adding a coat of arms and eagles. The modern flag is the fourth design, keeping the symbolic colors of green, white, and red while updating the coat of arms over time.