The East African country of Eritrea is one of the four countries including Somalia, Djibouti and Ethiopia who form the Horn of Africa region. These countries share commonalities between their peoples with regards to ethnic culture and identity as well as with religion.
Eritrea, or rather, the territory that is now known as Eritrea, has been known to the civilized world for thousands of years. The ancient kingdom of Aksum, (sometimes spelled Axum) comprised modern Eritrea and northern Ethiopia. Described as one of the greatest empires to ever exist in Africa, the Kingdom of Aksum lasted from around 100 CE to 940 CE, and extended across East Africa and beyond even reaching some parts of modern-day Djibouti and Sudan. Aksum remained the capital of Ethiopia until the seventh century CE.
The Aksumites were among the forebears of the people we would ordinarily describe as Nilotic these days. The Nilotic-Sudanese peoples and empires spread from the valley of the Nile right through the Eastern Great Rift area between the 5th millennium BC and 500 BC. Today, we can find Nilotic ethnic groups in Ethiopia right down to Tanzania.
The area that is Eritrea is bordered on the east by the Red Sea and the ocean became the marker by which the ancient Greek seafarers, described Eritrea. Erythra Thalassa was what the Greeks called the Red Sea and the land that laid immediately west of the sea was Erythra, meaning red.
The first formal adoption of Eritrea was in 1890 owing to Italian colonization. But before that, throughout the centuries, the ethnic peoples of this area chose their names for themselves even when Christianity was adopted by the mighty Aksum Kingdom and immigrants from across the Mediterranean settled in the area. Aksum embraced Christianity, practicing what has become the Ethiopian Orthodox tradition in the 4th century CE, beginning under the reign of King Ezana. Before converting to Christianity, the Aksumites worshipped and believed in multiple deities and gods including Astar, Beher, Meder/Medr, and Mahrem.
In 1993, the African peoples of the area asserted their independence and also chose to remain as Eritrea.