the east and centre of northern Somaliland must by now have been almost complete, reached the south. Their most important representatives here are the Bimal who, encountering the Digil, fought and overcame them, and eventually established themselves near Merca where they are today. Thus by the eighteenth century southern Somaliland as far south as the Juba River had assumed more or less its present ethnic complexion.
But the main Somali advance did not long halt at the Juba. Darod from the north and Ogaden continued to push south, often against the fierce resistance of those who had preceded them.10 Eventually these new northern invaders reached the Shebelle, and began to press heavily upon the Digil of the region early in the nineteenth century. Their progress was arrested, however, by the Rahanweyn, from about 1840 onwards under the strong leadership of the Geledi clan based on the Shebelle. This opposition forced these new Darod immigrants to move up to the Juba and brought them into contact with the Galla on the right bank of the river. Although so much of their territory had been lost in Somaliland, the Galla were still tenaciously clinging to what land was left to them, and from their centre at Afmadu, launched occasional raids across the river into what was now Somali territory. Their power in this region was thus by no means yet broken; and from time to time their raiding parties menaced the Somali religious centre at Bardera, founded in 1820 on the middle reaches of the Juba. Thus the new Darod invaders encountered a formidable neighbour whom, for the present, it was more expedient to appease than to provoke. Hence having gained their protection, parties of Darod clansmen crossed the river as clients and allies of the Oromo. The trans-Juban Oromo seem to have welcomed this new support and to have turned it to advantage in their relations with the turbulent Akamba and Masai to their west.
As time passed, the Darod movement continued and further Darod clansmen entered the area, sought alliance with the Galla, and crossed the river to join their kinsmen. Thus the strength of the Darod immigrants under Oromo protection gradually increased. This situation of uneasy Darod-Galla alliance, however, continued for some time and is that described by the French explorer Charles Guillain when he visited the southern Somali coast in 1847. Much the same position is recorded also by the ill-fated German traveller, von der Decken, who, in 1865, made history by sailing up the Juba River in his shallow-draught steamship Welf, only to founder in the rapids above Bardera.11 It was apparently in this same year that a severe epidemic of smallpox amongst the Galla provided the opportunity for which their Darod, neighbours had obviously been waiting. Almost immediately, the Darod fell upon their Galla hosts on all sides and inflicted very heavy losses. The few Oromo who survived fled to the south; and, by the turn of the century, most of the southern Galla had been cleared from the area, retaining footholds only at Wajir and Buna. A new factor now made itself felt in the form of desperate Ethiopian raids into the Ogaden and down the Juba. This, with further waves of new Somali immigrants – some of whom had sailed down the coast by dhow – maintained and even increased the Somali pressure. Indeed, by 1909, parties of Darod immigrants had pressed as far south as the Tana River with livestock estimated to number as many as fifty thousand beasts.
By 1912, when administrative and military posts were opened by the British in this turbulent northern part of the East African Protectorate, the situation was still fluid. The Darod were still on the move and were now seeking to dominate completely the whole region from Buna in the west, through Wajir, to the Tana in the south-east. Many of those non-Hamitic WaBoni hunters who had survived the tides of migration and battle had now become the serfs of the Darod, and most of the Warday Galla who remained had to be moved across the Tana River to prevent their extinction by the Somali. A good number, however, chose to stay with their former Darod subjects as clients, thus completely reversing the earlier position when the Oromo had been masters of Jubaland. To the west, the once powerful Ajuran, who after their defeat in the seventeenth century had been so ignominiously harried south-wards, had now lost much of their cohesion and were rapidly being infliltrated by other Somali. Finally, the southern Boran Galla were being thrust north-west by the continued Darod pressure.
By 1919, feeling between the Darod and those Warday Galla who had been moved across the Tana River reached such a pitch that it was again necessary for the British authorities to intervene. The consequence was an undertaking by both sides, known as the Somali–Orma (Galla) agreement, which allowed the Galla who remained with the Darod on the left bank to choose finally between accepting the formal position of serfs, or of moving across the river to join their free kinsmen. Those who decided to cross the Tana were obliged to leave behind them with their Somali patrons half the cattle which they had acquired during their bondage. Under these conditions it is perhaps not surprising that few of the Warday Galla moved.
Some twelve years later, further unrest broke out among the Galla subjects of the Darod, and a rumour began to circulate that the Somali were about to disregard the 1919 agreement. Whether on this account, or for other reasons, about eight hundred Oromo dependents with ten times as many head of livestock made a forlorn bid for freedom, trekking towards the Tana River at the very height of the dry season. The result was disastrous; nearly half their number perished, and the few who survived were ignominiously returned to the left bank of the river. In 1936, the agreement ended and the government of Kenya tacitly recognized that, except for those on the right bank of the Tana, the Warday Galla with whom the Somali had so long been struggling had been finally assimilated. Of the Oromo who had once occupied so much of this territory, only the Boran and Gabbra remained.
Thus ended the great series of migrations which, over a space of some nine hundred years, had brought the Somali from their northern deserts into the more fertile regions of the centre and south and finally into the semi-desert plains of northern Kenya. These movements had far-reaching social repercussions. Through contact with the Oromo and the absorption of those Galla who remained behind, and with an added leaven from the earlier Bantu communities, the Digil and Rahanweyn tribes emerged with their distinctive characteristics. From the Bantu they adopted cultivation, and from the Galla temporarily adapted their system of age-grades to their expanding military needs. In much the same way, the Darod who later crossed the Juba briefly assumed the Galla warrior age-grade system, and like the Rahanweyn, later discarded it.
At every stage in their expansion the tactics employed by the Somali were based upon their traditional evaluation of political power in terms of military strength. While at various times and places, small family groups and lineages, the spear-heads of the greater clan migrations, accepted the protection of their numerically dominant Oromo hosts, as soon as they were sufficiently strong they overthrew their patrons and made them their subjects. Wherever by force of numbers and arms they could, the Somali triumphed. Both sides seem to have relied on similar weapons, mainly spear and leather shield sometimes reinforced perhaps with bow and arrow. The Somali may, however, have enjoyed superiority in the use of a few matchlock guns, although it is doubtful if this was very significant. Probably, more significantly, their warriors were sometimes mounted on horseback, a technique which the Oromo later adopted and used to good effect in their massive migration into Abyssinia. Yet it was probably above all their overwhelming numerical superiority, and the dynamism which their movement acquired, which enabled the Somali to conquer so much territory at the expense of the Oromo. This and other considerations suggest that those Galla whom the Somali smote and put to flight – mainly Akishu, Raitu, and Arussi in the north, and Warday and Boran in the south – did not represent the main mass of the Oromo nation,12 but were rather sparsely distributed outlying groups far from their traditional homelands in the south-east of Ethiopia. Finally, in considering the character of the Somali expansion, it should be remembered that this was not a concerted operation under a single direction: it was a disjointed series of clan and lineage movements in which there were many cross-currents of migration as group jostled group in the search for new pastures. Nor does this sequence of Somali and Oromo movement exclude the possibility that the ultimate origins of both peoples may be traced to the same area on the upper reaches of the Juba river.
New European interest in the coast
While this great upheaval was taking place, with the exception for a time of Adal in the north and of states such as those of the Ajuran and Geledi in the south, it was only on the
