One of our best ancient sources for information about the gods and goddesses in Greek mythology - the Theogony of Hesiod - claims that Eirene was the daughter of Zeus and Themis. The poet Hesiod states:
"His second wife was radiant Themis; she bore the Seasons,
Lawfulness and Justice and blooming Peace,
who watch over the works of mortal men..."
(Hesiod, Theogony, 901-3)
In addition to being the child of Zeus and Themis, Eirene was therefore also a member of the group of goddesses who were referred to collectively as the Horae or Seasons. And as we can see from the quote above, the Horae were Eirene and her sisters Lawfulness (Eunomia) and Justice (Dike) according to the poet Hesiod.
The goddess Eirene was known by the name of Pax in Roman mythology.
Who's Who in Classical Mythology