 Complete the following phrase:  During the Era of Princes from 1755 to 1855, twenty-eight sovereigns reigned over the empire. Regional rivalries and internal conflicts were characteristics of the period, but no serious attempts were made by the rivals to separate from the empire. The Tigray Region gained strength, but Shewa became the regional powerhouse in the nineteenth century. Commerce was important in attracting British and French traders to the area from the mid-1830s. The first three-quarters of the nineteenth century political disorder continued to disrupt economic development. Conflicts with Egypt and attempts at Muslim expansion into Ethiopian territory continued into the twentieth century. In 1886, Addis Ababa became the capital of Shewa and three years later in 1889, Menelik II was crowned emperor. That year, the Italians declared a protectorate over the coastline of the Red Sea and the following year proclaimed Eritrea as an Italian colony. The terms of the Treaty of Wuchale, which the Italians used to insist their authority over Ethiopia, led to the 