Encyclopædia Britannica, Inc.A national flag is one of the most instantly recognizable symbols of a country’s identity. Usually people can tell which flag belongs to which country, especially given the prominence of flags at international sporting events, such as the World Cup and the Olympics. Sometimes, however, confusion can arise when two or more flags closely resemble each other. Here are nine sets of flags that exhibit varying degrees of similarity.

　　Chad and Romania

　　flags of Chad (top) and Romania (bottom)Encyclopedia BritannicaNone of the world’s national flags are as closely matched to each other as these two. Their design and size are almost identical, and only a close examination reveals slight shade differences between the blue, yellow, and red vertical stripes. The two came from totally different backgrounds. The Romanian flag dates from 1861, based on earlier versions with horizontal stripes. The flag of Chad was first hoisted in 1959 after the country had achieved independence from France. Its original design had a green stripe, but it too closely resembled the flag of Mali, so the blue stripe was substituted. Andorra has a similar flag as well, but it is distinguished by its centrally placed coat of arms.

　　Senegal and Mali

　　flags of Senegal (top) and Mali (bottom)Encyclopedia BritannicaSenegal’s flag and Mali’s flag share the same dimensions and basic green-yellow-red design of the vertical stripes, although there are slight shade differences in the colors. In addition, Senegal’s flag is distinguished by its green star in the central stripe. Guinea also has a similar flag, although its stripes are reversed, red-yellow-green.

　　Indonesia and Monaco

　　flags of Indonesia (top) and Monaco (bottom)Encyclopedia BritannicaThe flags for these two countries are almost identical—two horizontal stripes, red over white—but their dimensions differ: Indonesia’s flag has a height-to-width ratio of 2:3, while Monaco’s flag is 4:5. Both flags date back hundreds of years. Monaco’s flag is based on the heraldic colors in the shield of the Monegasque princely arms, and the flag of Indonesia dates back to its association with the Majapahit empire. Also similar to these two is the flag of Poland, although its stripes are reversed, white over red.

　　New Zealand and Australia

　　flags of New Zealand (top) and Australia (bottom)Encyclopedia BritannicaBoth flags are based on the British Blue Ensign (blue field with a Union Jack in the canton, or top inner corner) and feature a stylized version of the Southern Cross constellation. However, they differ in several ways: the design of the constellation (five white seven-pointed stars for Australia, four red-and-white five-pointed stars for New Zealand); the addition of a sixth, larger, “commonwealth” star on the Australian flag; and shade differences in the blues and reds. Nonetheless, the design similarities are one of the reasons why New Zealanders have considered replacing their flag.

　　Ireland and Côte d’Ivoire

　　flags of Ireland (top) and Côte d'Ivoire (bottom)Encyclopedia BritannicaThese two flags are somewhat less alike than those mentioned above, but their shared design of green, white, and orange vertical stripes can be confusing. The difference is that the green stripe on the Irish flag is on the hoist side (part of the flag closest to the flagpole), while the flag of Côte d’Ivoire is the reverse.

　　Norway and Iceland

　　flags of Norway (top) and Iceland (bottom)Encyclopedia BrtiannicaThe flag for each of these countries boasts an identical design but with the colors reversed. Both have their origins in the Danish flag, with its red field and white Scandinavian Cross. The Norwegian flag has a red field with a white-bordered blue cross, while Iceland’s flag has a blue field with a white-bordered red cross.

　　Venezuela, Ecuador, and Colombia

　　flags of Venezuela (top), Ecuador (middle), and Colombia (bottom)Encyclopedia BritannicaA flag of unequal yellow, blue, and red horizontal stripes was adopted by the new country of Gran Colombia in 1822. Although that country dissolved in 1830, the succeeding states of Colombia, Ecuador, and Venezuela incorporated that flag’s tricolor design into their respective flags. Those of Colombia and Ecuador retain the larger yellow stripe, while that of Venezuela has stripes of equal size. The Venezuelan flag is also distinguished by an arc of stars in its center and by the national coat of arms in the upper hoist corner. The Ecuadorian flag also depicts the country’s coat of arms, though in its center.

　　Luxembourg and the Netherlands

　　flags of Luxembourg (top) and the Netherlands (bottom)Encyclopedia BritannicaThe Dutch began using a red, white, and blue horizontally striped flag in the mid-17th century, the red being a substitution for the original orange stripe. This flag became the inspiration for the vertically striped French Tricolor after the French Revolution in 1789. Although Luxembourg lies close to the Netherlands, its flag was not derived from the Dutch flag but was developed independently. Luxembourg’s flag differs from the Dutch flag in being slightly longer and using a different shade of blue.

　　Slovenia, Russia, and Slovakia

　　flags of Slovenia (top), Russia (middle), and Slovakia (bottom)Encyclopedia BritannicaThe white-blue-red horizontally striped Russian flag dates to the end of the 17th century and was modeled on the Dutch tricolor. It, in turn, inspired the flag design for many countries of eastern and southern Europe. The two flags most closely resembling the Russian standard are those of Slovakia and Slovenia, which differ mainly in being longer than the Russian flag and incorporating their respective country’s coat of arms into the flag design. Flags that are variations on the Russian model include those of Croatia and Serbia, which use different patterns of red, white, and blue horizontal stripes.