Her father Achaeus was the second son of King Seleucus I Nicator and his first wife Apama I. Her name implies a strong Seleucid connection, as she was the namesake of her paternal aunt and her paternal great grandmother of this name.
Life and marriage
Her birth date is unknown, and little is known on her early life. Laodice I married her paternal first cousin Antiochus II Theos before 266 BC as his first wife. She married Antiochus II before he was the heir to the Seleucid throne.