After the Fulanis systematically captured Ilorin via the treason of Afonja the Field Marshall of the Oyo empire, the fulanis together with Malian and Hausa immigrants made Ilorin their territory. They had immense assistance from some Yoruba Ilorin Muslims which led to the sacking of the old Oyo Empire in 1835.
For administrative reasons, the fleeing Oyo citizens relocated the Oyo administrative centre from Oyo Ile to the present Oyo Ago. The Alaafin devolved the military power of the Oyo army into the hands of garrison commanders like Ogunmola, Kurunmi, Timi and Soun.
The Fulanis had sworn to dip the sword of Jihad into the Atlantic ocean and they were still not satisfied with their victory; they wished to extend their rule deep into the heart of Yoruba land and annex the whole coastal cities of Yorubaland into the Sokoto caliphate. Thus in 1840, they set to capture Osogbo , a Yoruba town. The Fulanis, under the command of Ali , the Hausa balogun of Ilorin, laid siege on Osogbo.
The fulanis got help from the Sokoto caliphate and other Arab/Tuareg mercenaries from across the sahel. The major war agenda of Sokoto caliphate was to destroy the Oyo monarchy and civilization completely before destroying all other Yoruba kingdoms for total subjugation just like the way they destroyed the Hausa civilization.
The fulani army could not pass through the Ogbomoso axis and Oke Ogun axis because the Ogbomoso army led by the Soun and Kurunmi Ajadi of Ijaye had blocked and sealed off that route making it impossible for them to launch any attack from the rear.
When the king of Osogbo realized that the Ilorins were too strong for the Osogbo army, he summoned the Ibadans for help. Ibadan immediately sent some auxiliaries to Osogbo under the command of Obele alias Mobitan , and Alade Abimpagun. As this force could not stop the Ilorins, another contingent was sent to Osogbo under a more experienced leader. But still the Ilorins won every battle and gained more ground. The fulanis controlled Osogbo for two years before the Oyo army led by Ibadan came to the battle field.
When the Ibadans realized that the Ilorins were becoming more threatening to Yoruba land, they sent a large and stronger force under Balogun Oderinlo to crush the intruding forces and Jammas of Ilorin . When Oderinlo and his men arrived at the battlefield, they realized that things had gone worse than they thought.
They could not show their faces in the open field for the fear of the Ilorin horses, and for about 20 days after their arrival at Osogbo, they could not fight outside the town thickets. Oderinlo suggested that Elepo, a brave Ibadan warrior was badly needed at the war-front. Elepo had been rejected by the war-chiefs of Ibadan for his actions at the late Agbamaja expedition.
As soon as the message from Oderinlo reached Ibadan, the Bashorun wished he could send Elepo to Osogbo but could not go against the wish of other war-chiefs. The Bashorun gave Elepo a cow to worship his god, Ori , and pray for the victory of Ibadan at the war-front.
At the war-front, the Ibadan could not attack the Ilorins during the day because Osogbo was practically in a plain and the Ilorin horses might have advantage of them with disastrous results.
They decided to attack at dusk when the Ilorins would no longer be able to use their horses. About 2:pm, the well prepared Ibadan army left the gate of Osogbo for the battlefield. They were to keep a strict watch and arrest anyone suspected to be a spy.
About a mile from the Ilorin camp, they halted and arranged the order of the attack.
The Osogbo army and the earlier auxiliaries were to handle the center of the battlefield, chiefs Abitiko and Labuju were to command the right wing, Balogun Oderinlo with the rest of the Ibadan war-chiefs were to form the left wing of the army. The Ilorin camp was then attacked at midnight. The watchword was “ Elo ni owo odo? ” (How much is the ferry fare?).
The reason this watchword was chosen was because the river Osun had to be crossed in entering Osogbo from the south, and anyone who could not tell this was likely to be an enemy.
Stampede engulfed the Ilorin camp as the Ibadan army set it on fire. The Ilorins could not offer the slightest resistance; they were smoked with the gunpowder of the Ibadan guns. Thousands of the Sokoto caliphate soldiers were slaughtered that day and thousands sold into slavery.
This attack was a success for the Ibadan. Some Ilorin war-chiefs were captured in the attack. Prominent ones were:
1. Jimba the head slave of the Emir;
2. One of the sons of Ali the commander in chief;
3. Chief Lateju;
4. Ajikobi the Yoruba Balogun of Ilorin.
The first two were released while the latter two, being Yoruba by birth, were regarded as traitors and were executed. This was a huge victory for the whole of Yoruba land.
After the Osogbo victory, Ibokun, an Ijesa town not far from Osogbo was taken by the Ibadans for being an ally of Ilorin. The Ibadans accused the Ijeshas, Ekitis and the Ondos for giving the fulanis free passage for their army and infantry in attacking another Yoruba town. The Ibadans then placed Ajeles on these Yoruba enclaves for the roles they played during the Osogbo war.
The violent imposition of the Ajeles on this Yoruba kingdoms led to the Ekiti parapo Civil War several years later.
Source: Proud To Be a Yoruba - OMO Oduduwa