In course of time, many city-states appeared. Some of the famous city-states were Adulis, Kohaito, Tekond’a, Keskese and Metera in Eritrea, and Yiha and Axum in Tigray. Each city-state had its own leader who was entitled Negasi (King). Negas is from Arabic word “Nejas” which means tax collector. At the end of 400 BC the city-states were amalgamated by war into one kingdom. This kingdom was called Axumite Kingdom. The leader of the amalgamated kingdom was entitled Neguse Negest (king of kings). The amalgamation was facilitated by the fact that all the city-states were sharing the same language, culture and religion.
The Axumite Kingdom comprised some parts of modern Eritrea and Tigray. Its permanent boundaries were Keren on the north, Alage Mountain on the south, River Tekeze on the west and Aduils along the Red Sea coast. However, at its zenith of expansion, it extended as far as Morowe around Khartoum on the west, southern Arabia on the east.