This story is from the book An Azanian Trio: Three East African Arabic Historical Documents which translates the manuscript titled Kitab Al Zunuj which is an account of the eastern coast of Africa that mentions the history of the Arabs Swahili and Somali peoples. The Ghaylan in the story are Galla or Oromo and were pagans during this time.
In the year 1282[1865–1866]the Somalis were pasturing the cattle of the Banū Qays Ghaylān at Kisimāyū and the surrounding districts. The Somalis were all at one in pasturing until one day the elder who was their leader mentioned, “The poor are enemies of the wealthy, so how is it that you are pasturing their herds and flocks like their slaves. It is better that we fight them and divide their wealth as spoil from God, and we shall be their masters by the generosity of God.” So the Somalis set about making war in the morning unawares, and they fought bitterly, and the Somālis were defeated and made reconciliation. The Banū Qays Ghaylān accepted the reconciliation. Then the Somalis wrote a letter to the leader in Birbira to urge them to come to Kisimayū and Wāmā, and the Somalis came in troops from Birbira and from Ḥāfūn, also going in ships to Kisimāyū, until the Somalis became numerous. They made war again on the Banū Qays Ghaylān and fought and the Somālis were defeated, and they made peace and the Banu Qays Ghaylān accepted the peace; and the Somālis returned to pasturing the cattle of the Banū Qays Ghaylān as at first. Then the Somālis wrote a letter that a large number of their people should come and perform the pastoral work deceitfully so that there might be gathered a great number. Then when the Somāli army had become very strong, they set about making preparations for the marriage and prepared a wedding feast, and invited about seventy of the Banū Qays Ghaylān leaders, valiant and brave. The Banū Qays Ghaylān accepted the invitation, and when the Ghaylān arrived they ate and drank and remained for the night; and the Somālis rose against the Ghaylān and slaughtered in the night seventy men while they slept. Then the Somālis kept on fighting them and they took their women, and they were sold in the districts of Fāza, Sīwī, Bata and Āmu. They spread out there and the Banū Qays Ghaylān fled and were made prisoners and the price of a girl was twenty riyals or less.
In the year 1282[1865–1866]the Somalis were pasturing the cattle of the Banū Qays Ghaylān at Kisimāyū and the surrounding districts. The Somalis were all at one in pasturing until one day the elder who was their leader mentioned, “The poor are enemies of the wealthy, so how is it that you are pasturing their herds and flocks like their slaves. It is better that we fight them and divide their wealth as spoil from God, and we shall be their masters by the generosity of God.” So the Somalis set about making war in the morning unawares, and they fought bitterly, and the Somālis were defeated and made reconciliation. The Banū Qays Ghaylān accepted the reconciliation. Then the Somalis wrote a letter to the leader in Birbira to urge them to come to Kisimayū and Wāmā, and the Somalis came in troops from Birbira and from Ḥāfūn, also going in ships to Kisimāyū, until the Somalis became numerous. They made war again on the Banū Qays Ghaylān and fought and the Somālis were defeated, and they made peace and the Banu Qays Ghaylān accepted the peace; and the Somālis returned to pasturing the cattle of the Banū Qays Ghaylān as at first. Then the Somālis wrote a letter that a large number of their people should come and perform the pastoral work deceitfully so that there might be gathered a great number. Then when the Somāli army had become very strong, they set about making preparations for the marriage and prepared a wedding feast, and invited about seventy of the Banū Qays Ghaylān leaders, valiant and brave. The Banū Qays Ghaylān accepted the invitation, and when the Ghaylān arrived they ate and drank and remained for the night; and the Somālis rose against the Ghaylān and slaughtered in the night seventy men while they slept. Then the Somālis kept on fighting them and they took their women, and they were sold in the districts of Fāza, Sīwī, Bata and Āmu. They spread out there and the Banū Qays Ghaylān fled and were made prisoners and the price of a girl was twenty riyals or less.