Despite being incorporated into the Ifat Sultanate, Adal managed to maintain a source of independence under Walashma rule, alongside the provinces of Gidaya, Dawaro, Sawans, Bali, and Fatagar.

[32] In the late 14th century, the Ethiopian Emperor Dawit I collected a large army, branded the Muslims of the surrounding area "enemies of the Lord", and invaded Adal.

As a result, Yeshaq and his men fled to the Blue Nile region over the next five months, while Jamal ad Din's forces pursued them and looted much gold on the way, although no engagement ensued.

The young Sultan Jamal ad-Din II at the end of his reign had outperformed his brothers and forefathers in the war arena and became the most successful ruler of Adal to date.

[47] However, this ambitious campaign ended in disaster when Emperor Zara Yaqob defeated Sultan Badlay at the Battle of Gomit and pursued the retreating Adalites all the way to the Awash River.

[49] Adal's Emirs, who administered the provinces, interpreted the agreement as a betrayal of their independence and a retreat from the polity's long-standing policy of resistance to Abyssinian incursions.

[52][53] Emperor Na'od and Sultan Muhammad ibn Azhar ad-Din tried to remain at peace, but their efforts were nullified by the raids which Emir Mahfuz constantly made into Christian territory.

He was stimulated by emissaries from Arabia who proclaimed the jihad (holy war), presented him with a green standard and brought in arms and trained men from Yemen.

The older generation of the Muslims headed by the Walashma, indifferent to religion and ready to come to terms with Abyssinia, were staunchly opposed by the Harari and Harla religious aristocracy led by fanatic warlike emirs.

However, Sultan Abu Bakr ibn Muhammad, who had transferred the capital from Dakkar to Harar in 1520, profiting off the prestige that the hereditary monarchy still held, recruited bands of Somali nomads, ambushed Abun Adashe at Zeila and killed him in 1525.

Fervor for the jihad had not yet overcome the forces inherent in nomadic life, Ahmad had to undertake several campaigns to restore order in the Somali territory which would constitute his manpower reserve.

[57][58][59] According to sixteenth century Adal writer Arab Faqīh, in 1529 Imam Ahmad ibn Ibrahim al-Ghazi finally decided to embark on a conquest of Abyssinia, he soon met the Abyssinians at the Battle of Shimbra Kure where he would win a decisive victory.

In 1535 Ahmad, in control of the east and center of Abyssinia invaded Tigray where he encountered fierce resistance and suffered some reserves, but his advance was not stopped, his armies reached the coasts of Medri Bahri and Kassala where they made contact with the Muslim Beja tribes of the north that had formerly paid tribute to the Ethiopian Empire.

The Emperor did not hesitate to take the offensive and won a major victory at the Battle of Wayna Daga when the fate of Abyssinia was decided by the death of the Imam and the flight of his army.

The invasion force collapsed like a house of cards and all the Abyssinians who had been cowed by the invaders returned to their former allegiance, the reconquest of Christian territories proceeded without encountering any effective opposition.

[78] Ethiopian historian Taddesse Tamrat states that Adal's central authority in the fourteenth century consisted of the Argobba, Harari and Silt'e people.

[79] Professor Donald N. Levine, an important figure in Ethiopian Studies, described the Adal Sultanate as consisting of many ethnic groups, but primarily Somalis and Afars.

[93] Among the earliest mentions of the Somali by name has come through a victory poem written by Emperor Yeshaq I of Abyssinia against the king of Adal, as the Simur are said to have submitted and paid tribute.

"[94] According to Leo Africanus (1526) and George Sale (1760), the Adelites were of a tawny brown or olive complexion on the northern littoral, and grew swarthier towards the southern interior.

[85] British historian John Fage states Walasma leaders moving their capital from Ifat region to Adal set in motion the evolution of Harari and Argobba language within Harar and its environs.

Agricultural produce included three main cereals, wheat, sorghum and teff, as well as beans, aubergines, melons, cucumbers, marrows, cauliflowers and mustard.

Furthermore, the citizens had many horses and reared cattle of all kinds, as a result they had plenty of butter, milk and flesh, as well as a great store of millet, barley and fruits; all of which was exported to Aden.

Created a lucrative caravan trade route between Ethiopian interior, the Hararghe highlands, Eastern Lowlands and the coastal cities such as Zeila and Berbera.

Many of the historic cities in the Horn of Africa such as Abasa, Amud, Awbare and Berbera flourished under its reign with courtyard houses, mosques, shrines, walled enclosures and cisterns.

[117] The horsemen of Adal wore protective helmets that covered the entire face except for the eyes, and breastplates on their body, while they harnessed their horses in a similar fashion.

Numerous such historical edifices and items are found in the northwestern Awdal province of Somaliland, as well as other parts of the Horn region where the polity held sway.

[123] According to archaeologist Jorge Rodriguez, substances located in western northern Somalia indicate outposts were mainly established during the Adal Sultanate, and don't predate the ruins found in ancient Islamic regions of Ifat or Harar plateau, this he states reaffirms the notion that modern eastern Ethiopia is where the principal Muslim kingdoms materialized.

The fine celadon ware was found either lying on the surface, or buried at a depth of seven and a half inches, or ensconced within dense middens four to five feet high.

They were adorned with tendril scrolls on a bluish ground and ornamented with black spotting, while other bowls had floral patterns outlined by grey or black-blue designs.

[127] Additionally, local tradition identifies the archaeological site of Tiya in central Ethiopia as Yegragn Dingay ("Gran's stone") in reference to Imam Al-Ghazi.