Oromo expansion
The Oromo expansions or the Oromo invasions, were a series of expansions in the 16th and 17th centuries by the Oromo primarily documented by the Gamo monk Bahrey, but also mentioned in other Christian, Muslim and Portuguese records. 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, many factors – mostly the wars between the Adal Sultanate and the Ethiopian Empire – would further encourage the numerous Oromo tribes to expand towards what is now central and eastern Ethiopia.
History
A medieval European, the Portuguese missionary Manuel de Almeida, upon learning of the invasion, noted that both Adal and Abyssinia were experiencing divine retribution:Legend of Liqimssa
The legend of Liqimssa is an ancient legend stemming from the Borana sect of the Oromo peoples that is credited as having been one of the main motivations for the beginning of the Oromo expansions. The Liqimssa roughly translates to "The Swallower" and was told to be a beast that consumed people one by one until there was nobody left to fight against it. It is meant to embody "hunger", and the story represents how a powerful entity will consume all there is around it until the "land of plenty" is left barren and empty. The legend is interpreted by Mohammed Hassen to be the embodiment of the Christian kingdom's growing power and influence in the regions directly north of the Oromo homelands.Early expansions
The early expansions 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 Gadaa of Meslé. Gudifecha adoption tradition also lead to massive diversification within Oromo populations as they expanded during the 16th century.Mélbah (1522–1530) and Mudena (1530–1538)
According to Bahrey, the earliest Oromo expansion occurred under the Oromo luba Melbah, during the time of Emperor Dawit II. He states that they invaded the neighbouring Bale, in the southeast, just before the invasions of Ahmad ibn Ibrahim al-Ghazi of Adal in the north. These early incursions 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. The reason for the Oromo returning after their short conquests is that the Christian and Muslim kingdoms that surrounded Oromo pastoralists were deeply embroiled in wars. Instead of engaging with either kingdom directly, they targeted isolated communities that would go unnoticed and allowed their enemies to destroy each other without Oromo intervention.Three stages of Oromo movements
By the 1530s, the Oromo pastoralists had developed a three-staged method for territorial expansion; "scouting, night time surprise attack and settlement". The introduction of scouting teams shows that the Oromo pastoralists had quickly become accustomed to border warfare. The night time attacks that would come to follow were unceasing and relentless, stripping the community of their "booty" and killing a large amount of the warrior class, then escaping before dawn as to avoid being followed back to their base camps. Once the community under siege was broken down enough to be settled without resistance, the remaining peoples would quickly be integrated through Moggaasaa, having their status, material goods and general livelihoods returned to them. The remaining warriors would join the Oromo gada's troops. With each period of adoption into the fighting class, the Oromo's knowledge of the local terrain would increase drastically.Kilolé (1538–1546)
After the death of Ahmed Gragn, Kilolé resumed his predecessor's raids and pierced further into Ethiopian territory. Aided by the weakening of both the Ethiopian Empire and the Adal Sultanate, he raided as far as the province of Dawaro, north of Bali. Again, however, after each raid, the parties returned to their villages. Bahrey's dating might, however, be off, as Shihab ad-din, who had written a decade before Ahmed Gragn's death, noted a locality named Werre Qallu, an Oromo name, in the province of Dawaro. Francisco de Almeida, however, agreed with Bahrey's dating, by affirming that the Oromo first began migrating around the time of Ahmed Gragn's invasion.Bifolé (1546–1554)
During the time of luba Bifolé, the Oromo migration achieved its first major success. All previous movements had been minor raids on neighbouring provinces, but under Bifolé, new raids were undertaken that began to weaken Ethiopian control. All of Dewaro was pillaged, and Fatagar to its north was attacked for the first time. Furthermore, according to Bahrey, the inhabitants of the pillaged areas were enslaved to become gebrs, a term referring more precisely to "tax-paying serfs", similar to the serfs in Ethiopia during feudal times. Emperor Gelawdewos, however, campaigned in the south as a result of those attacks. According to his chronicle, the Emperor defeated the Oromo incursions and made subject to his rule those he captured, which prevented further attacks for some time, with further incursions reduced to skirmishes. The initial attacks were significant, however, on a much larger and more devastating scale to the Ethiopian dynasty. Despite his reprisals, Gelawdewos was troubled and was forced to settle refugees in a town of Wej, north of Lake Zway, around 1550–1551.Settlement
Meslé (1554–1562)
Meslé's time represent a fundamental change in the expansion of the Oromo. Newly-taken territories were permanently settled by Oromo for the first time, and mules and horses began to be ridden. The adoption of horseback riding from the north greatly increased the Oromo fighting power and put them on par with Ethiopian troops, who were largely equipped with firearms. In the new phase of migration adopted under Meslé, the Oromo defeated Emperor Gelawdewos's Jan Amora corps, allowing them to pillage a number of towns. Instead of returning to their homelands, however, they stayed in the new territories. Gelawdewos campaigned against the Oromo as a result, defeating them at 'Asa Zeneb, but he was nevertheless unable to drive them from the frontier provinces and continued to build the new town in Wej for new refugees.Oromo expansions were not restricted to Ethiopian territories either, as activities against Adal were also pursued. The forces of Nur ibn Mujahid, the Amir of Harar, for instance, were soundly defeated by the Oromo in an ambush at the Battle of Hazalo. According to Bahrey, there had been "no such slaughter since the Oromo first invaded".
Harmufa (1562–1570) and Robalé (1570–1578)
During the luba of Harmufa rule, the Oromo advanced even deeper into Ethiopian territory. With the use of horses, they were able to attack the province Amhara, and Angot. Further advances were made under Robalé during whose time Shewa was pillaged and Gojjam attacked. For the first time, Oromo advances were devastating core Ethiopian provinces, but their earlier incursions had been simply against frontier provinces. Despite the deeper attacks, the core provinces remained under Ethiopian control, and Emperor Sarsa Dengel carried out punitive expeditions in return. One such reprisal in 1573 involved the engagement of the Oromo near Lake Zway in a frontier province. He defeated them, took their cattle and distributed the herd among his subjects, who were described in his chronicle as "becoming rich" as a result.Michelle Gadaa invasion of Adal period (1562–1579)
At the same time, Barento Oromo groups attacked the Adal Sultanate, which was greatly weakened by its wars with the Christian Ethiopians leading to no potential resistance. In the 16th century, the Oromo began their invasion of Harar region occupying as far as Hubat which forced the Adal Sultanate to erect a wall around Harar the capital city of the principality. By the late sixteenth century other Adalite towns in the Harar region also began to construct ramparts such as Gidaya, and Dakkar. According to Harari chronicles the combination of the Oromo invasion which followed drought led to the destruction of several towns and regions including Sim, Shewa, Negeb, Hargaya and Dakkar. Oromo invasions in the Harar region were followed by epidemic and food shortages in Adal's capital Harar leading to massive loss of life which included Adal leader Nur ibn Mujahid among the casualties in 1567.The Oromo attacks on the Harar plateau did not let up in 1572, as recounted in a Harari chronicle.
The Adal Sultanate would move its capital to Aussa due to the Oromo provocation in 1577 however Adal leader imam Muhammad Gasa would be killed in battle against the Oromo in 1583. In the Chercher region of Harar, Ittu Oromo would incorporate the Harari and plausibly the Harla people. Its presumed the last remaining pre Oromo invasion inhabitants the Harla people were able to survive due to the fortification of the city of Harar. Scholar Christopher Ehret stated the greater part of the Adal Muslim population were assimilated by the Oromos with the exception of pockets of Harari and Argobba semitic speakers. According to historian Mohammed Hassen and others, the Oromo invasions were devastating for the Harari people and is one of the major reasons for their diminished populace.
The Hawiye and Dir clans became the predominant inhabitants of Hararghe Highlands in the 16th century after the weakening of Adal. The Oromos took advantage of the crippling state and decided to also invade and to occupy the Hararghe Highlands and assimilate with Somali clan population of Jarso, Akisho, Gurgura, Nole, Metta, Oborra, and Bursuk. All were sub-clans of Dir, a major Somali clan, and were later confederated into Oromo tribe, the Afran Qallo clan.
According to I. M. Lewis, in the early 1600s Ughaz Ali Makahil successfully repelled the Oromo Invasions in modern northern Somalia.