Anthusa of Constantinople was a Byzantine nun born in the mid-eighth century, the daughter of Emperor Constantine V. Although her father initially pressured her to marry, she chose a life of monasticism instead. After the emperor's death, she dedicated her wealth to supporting orphans and the impoverished. She eventually established the Omonoia Monastery in Constantinople, which was noted for its disciplined way of life. She is recognized as a saint in both the Catholic and Eastern Orthodox traditions.