The Kingdom of Aksum, also known as the Kingdom of Axum or the Aksumite Empire, is an important trading nation from approximately 100 to 940 in northeastern Africa, with its capital at the city of Axum (Aksum).

The kingdom is centered in what is now northern Ethiopia, and spans modern-day Eritrea, eastern Sudan and Yemen at its height during the reign of Kaleb of Axum.

Emerging from the earlier Dʿmt civilization, the kingdom was likely founded in the early first century.

Pre-Aksumite culture developed in part due to a South Arabian influence, evident in the Aksumite use of Ancient South Arabian script and the practice of Ancient Semitic religion.

However, the Geʽez script comes into use by the fourth century, and as the kingdom becomes a major power on the trade route between Rome and India, it enters the Greco-Roman cultural sphere and begins to use Greek as a lingua franca.

It is through this that the Kingdom of Aksum adopts Christianity as the state religion in the mid-fourth century under Ezana of Axum.

Following their Christianization, the Aksumites cease construction of stelae.

The kingdom is considered one of the ancient world's four great powers by third-century Persian prophet Mani, alongside Persia, Rome, and China.

Beginning with the reign of Endubis, Aksum mints its own coins—the first to be minted in sub-Saharan Africa—which have been excavated in locations as far as Caesarea and southern India.

The kingdom continues to expand throughout late antiquity, taking parts of the Kingdom of Kush for a very short period of time, from whom it inherits the Greek exonym "Ethiopia", which it uses as early as the fourth century.

Aksumite dominance in the Red Sea culminates during the reign of Kaleb of Axum, who, at the behest of Eastern Roman emperor Justin I, invades the Himyarite Kingdom in Yemen in order to end the persecution of Christians by the Jewish king Dhu Nuwas.

With the annexation of Himyar, the Kingdom of Aksum is at its largest territorial extent, but the territory is soon lost in the Aksumite–Persian wars.

In the seventh century, the Muslims, who originated in Mecca, seek refuge from Quraysh persecution by traveling to Aksum (Abyssinia), a journey famous in Islamic history as the First Hijra.

The kingdom's slow decline has begun by the seventh century, at which point currency ceases to be minted.

The Persian (and later Muslim) presence in the Red Sea causes Aksum to suffer economically, and the population of the city of Axum shrinks.

Alongside environmental and internal factors, this has been suggested as the reason for the decline.

Aksum's final three centuries are considered a dark age, and through uncertain circumstances, the kingdom collapses around 960.

Despite its position as one of the foremost empires of late antiquity, the Kingdom of Aksum falls into obscurity as Ethiopia remains isolated throughout the Middle Ages.