Medri Bahri

Medri Bahri () was a medieval Habesha Kingdom, also known as Mareb Melash (beyond the river Mareb). It was situated in modern-day Eritrea and northern Ethiopia, and was ruled at times by the Bahri Negus (also called the "Bahri Negasi," "Bahr Negash", or "king of the sea" in English). It lasted from the 12th century AD to the Italian colonization in 1889. It survived several threats like the invasion of Imam Gran and the Ottoman Red Sea expansion, albeit Medri Bahri irretrievably lost its access to the Red Sea due to the latter. The relation to the Ethiopian empire in the south varied from time to time, ranging from autonomy, to tributary status, to de facto annexation. At first the residence of the Bahr Negash was at Debarwa, but during the 17th century it was relocated to the village of Tsazega due to the same-named clan taking control of the kingdom. 
In 1680, Medri-Bahri’s political process was described by the German scholar J. Ludolph as being a Federal Republic. This republic political process was found no where else in the horn of Africa and was distinct to the kingdom of Medri Bahri.
History.
Origins and turbulent 16th century.
After the Aksumite empire, the area from the Eritrean highlands to the Red Sea was known as "Ma'ikele Bahr" ("between the seas/rivers," i.e. the land between the Red Sea and the Mereb river). It was later renamed as the domain of the "Bahr Negash" ("Ruler of the sea"), the Medri Bahri ("Land of the Sea", "Sea land" in Tigrinya, although it included some areas like Shire on the other side of the Mereb, today in Ethiopia). The entire coastal domain of Ma'ikele Bahri was under the Adal Sultanate during the reign of Sultan Badlay. The first time the title "Bahr Negash" appears is during the reign of emperor Zara Yaqob (r. 1433-1468), after his reconquest on behalf of the Ethiopian Empire, who perhaps even introduced that office. His chronicle explains how he put much effort into increasing the power of that office, placing the Bahr Negash above other local chiefs and eventually making him the sovereign of a territory covering the Shire, a region south of the Mareb river in what is now Ethiopia, The highlands(ከበሳ) of what is now Eritrea including Hamasien, Seraye,
 To strengthen the imperial presence in Medri Bahri, Zara Yaqob also established a military colony consisting of Maya warriors from the south of his realm.
In the 1520s, Medri Bahri was described by the Portuguese traveller and priest Francisco Alvares. The current Bahr Negash bore the name Dori and resided in Debarwa, a town on the very northern edge of the highlands. Dori was an uncle of emperor Lebna Dengel, to whom he paid tribute. These tributes were traditionally paid with horses and imported cloth and carpets. Dori was said to wield considerable power and influence, with his kingdom reaching almost as far north as Suakin, plus he was also a promoter of Christianity, gifting the churches everything they needed. By the time of Alvares' visit, Dori was engaged in warfare against some Nubians after the latter had killed his son. The Nubians were known as robbers and generally had a rather bad reputation. They originated somewhere five to six days away from Medri Bahri, possibly Taka (A historical province named after Jebel Taka near modern Kassala).
The Bahre-Nagassi ("Kings of the Sea") alternately fought with or against the Abyssinians(Modern day Ethiopia) and the neighbouring Muslim Adal Sultanate depending on the geopolitical circumstances. Medri Bahri was thus part of the Christian resistance against Imam Ahmad ibn Ibrahim al-Ghazi of Adal's forces, but later joined the Adalite states and the Ottoman Empire front against Abyssinia in 1572. During the 16th century said Ottomans also began making inroads in the Red Sea area.
The territory became an Ottoman province or eyalet known as the Habesh Eyalet. Massawa served as the new province's first capital. When the city became of secondary economic importance, the administrative capital was soon moved across the Red Sea to Jeddah. Its headquarters remained there from the end of the 16th century to the early 19th century, with Medina temporarily serving as the capital in the 18th century. Turks briefly occupied the highland parts of Baharnagash in 1559 and withdrew after they encountered resistance and pushed back by the Bahrnegash and highland forces. In 1578 they tried to expand into the highlands with the help of Bahr negus Yeshaq who had switched alliances due to power struggle, and by 1589 once again they were apparently compelled to withdraw their forces to the coast. After that Ottomans abandoned their ambitions to establish themselves on the highlands and remained in the lowlands until they left the region by 1872.
17th century-1890.
The Scottish traveler James Bruce reported in 1770 that Medri Bahri was a distinct political entity from Abyssinia, noting that the two territories were frequently in conflict.
The kingdom was briefly occupied in 1879, when Ethiopian Ras Alula seized control of the region after he broke his promise of reconciliation to Ras Woldemichael Solomon and imprisoned him. This occupation was nonetheless shortlived as the region became an Italian colony in 1890.
Geography.
At its peak, the Kingdom of Medri Bahri stretched from the Red Sea to the Mereb River and beyond, covering areas of Shire (Including Inda Selassie) and its surrounding regions. This vast region was subdivided into three main provinces, namely Akele Guzai, Hamassien and Serae. Of these three, Serae was the most politically important district, as the most influential and important people took up residence there. As a consequence, this was also the wealthiest, the best maintained and the best protected district. In the language of Tigrinya language "Medri Bahri" means "Land of the Sea" in reference to the Red Sea which Eritrea has a long coastline of this sea. This kingdom had a border to the south with Tigray Region, a province of the Ethiopian Empire also known as Abyssinia.
Demographics.
Medri Bahri was composed of the following modern ethnic groups: Tigrinya people, Saho people, Tigre people. Irob people