Iyasu II or Joshua II (Ge'ez ኢያሱ) was Emperor (throne name Alem Sagad, Ge'ez ዓለም ሰገድ ʿAläm Sägäd, "to whom the world bows") of Ethiopia, and a member of the Gondar branch of the Solomonic dynasty. He was the son of Emperor Bakaffa and Empress Mentewab (also known by her Baptismal name of Welete Giyorgis).
The Empress Mentewab played a major role in Iyasu's reign, perhaps against her will. Shortly after he was proclaimed Emperor, a rival claimant assaulted the Royal Enclosure for eight days, only leaving the capital Gondar when an army of 30,000 from Gojjam appeared. Although the rebels failed to penetrate its walls, nonetheless much of Gondar was left in ruins. Instead of taking the title of regent upon the succession of her underage son, Empress Mentewab had herself crowned as co-ruler, becoming the first woman to be crowned in this manner in Ethiopian history. Empress Mentewab wielded significant authority throughout the reign of her son, and well into the reign of her grandson as well.