Italy's search for colonies continued until February 1886, when, by secret agreement with Britain, it annexed the port of Massawa in Eritrea on the Red Sea from the crumbling Egyptian Empire. Italian annexation of Massawa denied the Ethiopian Empire of Yohannes IV an outlet to the sea. At the same time, Italy occupied territory on the south side of the horn of Africa, forming what would become Italian Somaliland. However, Italy coveted Ethiopia itself and, in 1887, Italian Prime Minister Agostino Depretis ordered an invasion, leading to the Eritrea War. This invasion was halted after the loss of five hundred Italian troops at the Battle of Dogali. Depretis's successor, Prime Minister Francesco Crispi signed the Treaty of Wuchale in 1889 with Menelik II, the new emperor. This treaty ceded Ethiopian territory around Massawa to Italy to form the colony of Italian Eritrea, and – at least, according to the Italian version of the treaty – made Ethiopia an Italian protectorate. Relations between Italy and Menelik deteriorated over the next few years until the First Italo-Ethiopian War broke out in 1895, when Crispi ordered Italian troops into the country. Vastly outnumbered and poorly equipped, the result was a decisive defeat for Italy at the hands of Ethiopian forces at the Battle of Adwa in 1896. The Ethiopians were supported by Russian advisers and equipment, as well as by a unit of Russian volunteers. The death toll was 6,889, including 4,133 Italians. The Ethiopians counted at least 4,000 dead and 10,000 wounded. Total Italian, Eritrean, and Somali deaths, including those from disease, were estimated at 9,000.