The Great Oromo Migrations

The Great Oromo migrations, also known as the Oromo migrations, were a series of expansions in the 16th and the 17th centuries by the Oromo people from southern Ethiopia, namely the contemporary Borana and Guji zones, into more northerly regions of Ethiopia. The expansion had a profound impact on subsequent historical events occurring in Ethiopia.

Because the Oromo did not keep a written record of the migrations, this article must refer to Ethiopia, Portuguese, and Arabic sources for the reasons behind the migrations. In particular, a 16th-century Tigray monk named Bahrey is the foremost source on the migrations. Written in Ge'ez, his book was called the History of the Galla (Ge'ez: ዜናሁ ፡ ለጋላ zēnahu legalla), "Galla" being an older name for "Oromo" that is now considered a pejorative. This book was written in 1593 and details the expansions from 1522 to his age. In addition to his book, further information can be gleaned from other contemporaries such the Ethiopian monk Abba Paulos, Shihab ed-Din's Futuh al-Habasha "Conquest of Abyssinia", João Bermudes, Francisco de Almeida, Jerónimo Lobo, and various royal chronicles (e.g. those of Gelawdewos, Sarsa Dengel, and Susenyos I, though that of Sarsa Dengel may have been written by Bahrey).

The early migrations were characterized by sporadic raids by the Oromo on the frontiers of the Ethiopian kingdom. After capturing cattle and other booty, the raiding parties would quickly return to their homelands. Actual settlement of new territories would not begin until the lubaship of Meslé. Luba (Ge'ez ሉባ lūbā) is an "appointed" head of one of the five groups of the Oromo clans.

According to Bahrey, the earliest Oromo migrations occurred under the Oromo luba Melbah, during the time of Emperor Lebna Dengel. He states that they invaded the neighboring Bale in the Southeast just before the invasions of Ahmad ibn Ibrahim al-Ghazi of Adal (also known as Ahmed Gure) in the north. These early incursions (Oromo: razzia) were limited, however, as the encroaching groups returned to their homeland near the Shebelle River after each raid. Raids continued under Mudena past the Wabi Shebelle, but these groups also returned home shortly.

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