Oromo expansion

The Oromo expansions, also known as the Oromo migrations or the Oromo invasions (in older historiography, Galla invasions), were a series of expansions in the 16th and 17th centuries by the Oromo. Prior to their great expansion in the 16th century, the Oromo inhabited only the area of what is now modern-day southern Ethiopia and northern Kenya. Over the centuries due to many factors, mostly the wars between Adal Sultanate and Ethiopia would further encourage the numerous Oromo tribes to expand towards central and eastern modern Ethiopia.