"A History of Ancient Greece" explains that in the context of Ancient Greece, affranchisement came in many forms. A master choosing to free his slave would most likely do so only "at his death, specifying his desire in his will". In rare cases, slaves who were able to earn enough money in their labour were able to buy their own freedom and were known as "choris oikointes". Two 4th-century bankers, Pasion and Phormio, had been slaves before they bought their freedom. A slave could also be sold fictitiously to a sanctuary from where a god could enfranchise him. In very rare circumstances, the city could affranchise a slave. A notable example is that Athens liberated everyone who was present at the Battle of Arginusae (406 BCE).