What African country was Eritrea formerly a part of?

Explanation

Eritrea is a country in the Horn of Africa. It has around 5 million inhabitants and covers an area of 121,320 km². It borders Sudan to the west, Ethiopia to the south and Djibouti to the southeast. To the east and northeast, the country borders the Red Sea. In the past, the area was an Italian colony, and was also part of Ethiopia for a while. Eritrea gained independence from the latter in 1993, with self-governance from 1994.