daughter of Julius Constantius

An unnamed daughter of Julius Constantius was the first known wife of Constantius II. Family She is mentioned in the "Letter To The Senate And People of Athens" by Emperor Julian to have been a sister of Constantius Gallus. When mentioning the execution of Gallus by orders of Constantius II, Julian lists the several ways the two men were related. "Constantius gave over to his most inveterate enemies, his own cousin, the Caesar, his sister's husband, the father of his niece, the man whose own sister he had himself married in earlier days". Gallus was a son of Julius Constantius and his first wife Galla. She is assumed to be a full sister of Gallus. Julius Constantius was a son of Constantius Chlorus and Flavia Maximiana Theodora. He was a paternal half-brother of Constantine I. In 337, Constantine I died. Several of his relatives were killed shortly after his death. Julius Constantius was among them. The "History of the Arians" (358) by Athanasius of Alexandria reports on Constantius II having killed his father-in-law. Though Constantius had two later marriages, this is considered a reference to Julius Constantius. "The common feelings of humanity could not induce him to spare even his own kindred. His uncles he slew; his cousins he put out of the way; he commiserated not the sufferings of his father-in-law, though he had married his daughter, or of his kinsmen". A brother is considered to have been assassinated with their father in 337. Julian the Apostate was a younger, paternal half-brother to this Empress.