Please rephrase your question so that we know what event on or near the Euphrates you mean. The river Euphrates has been there from long before the dawn of civilization until the present day.
Mesopotamia has two rivers, the Tigris and the Euphrates.
No empire based in Egypt ever controlled the Euphrates River, but the Ayyubid Empire, which was based in Egypt came the closest to doing so in the mid-1100s.
The Tigris, the Euphrates, the Diyala and the Khasa are the main ones.
Euphrates.
The Tigris and Euphrates Rivers flow into the Persian Gulf.
The Tigris and Euphrates rivers
Those two rivers are the Euphrates and Tigris.
The Euphrates is in Iraq.
The Euphrates River
Mesopotamia has the Euphrates and Tigris Rivers.
The Tigris and the Euphrates were the main rivers of the fertile crescent
The Euphrates river ends in Iraq