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The flag of Eritrea has three horizontal stripes of green, blue, and red with a gold olive branch in the center.

Eritrea

ኤርትራ

Population: 5,352,000

Region: Africa

Subregion: Eastern Africa

Capital: Asmara

Top Level Domain: .er

Currencies: Eritrean nakfa

Border countries

The flag of Djibouti has two equal horizontal bands of light blue and green with a white isosceles triangle based on the hoist side containing a red five-pointed star.

Djibouti

Population: 988,002

Region: Africa

Capital: Djibouti
The flag of Ethiopia has three horizontal stripes of green, yellow, and red with a blue circle and a yellow star in the center.

Ethiopia

Population: 114,963,583

Region: Africa

Capital: Addis Ababa
The flag of Sudan has three horizontal stripes of red, white, and black with a green triangle on the left side.

Sudan

Population: 43,849,269

Region: Africa

Capital: Khartoum