Atticus II was born on 2 April 842 in Constantinople to Atticus I and Aelia of Venice. He was raised by his parents in Constantinople until 853, at which point he relocated to Athens to being studying under the strategos of the Hellas theme. While studying under the stragegos, he learned of military tactics and of governing a population. By the time his father died and it was time for Atticus II to inherit the throne, he was 21 years of age.