Valerius Valens

Aurelius Valerius Valens (died March 1, 317) was Roman Emperor from late 316 to March 1, 317. Valens had previously been "dux limitis" (duke of the frontier) in Dacia.
In the first civil war between Licinius and Constantine I, the latter won an overwhelming victory at the battle of Cibalae on October 8, 316 (some historians date it in 314). Licinius fled to Adrianople where, with the help of Valens, he gathered a second army. There, early in December 316, he elevated Valens to the rank of Augustus, presumably in order to secure his loyalty. Much later, Licinius would use the same trick (with just as little success) in the second civil war with Constantine, by appointing Martinian co-emperor.
Despite the literary sources referring to Valens as a junior emperor (Caesar), the numismatic evidence indicates his Augustan rank.
After Licinius's indecisive defeat at Campus Ardiensis in later 316 / early 317, Constantine was still in the dominant position; from which he was able to force Licinius to recognize him as the senior emperor, depose Valens and appoint their sons as Caesars. According to Petrus Patricius, he explicitly expressed his anger at the elevation of Valens by saying the following to the envoy of Mestrianus:
The emperor made clear the extent of his rage by his facial expression and by the contortion of his body. Almost unable to speak, he said, "We have not come to this present state of affairs, nor have we fought and triumphed from the ocean till where we have now arrived, just so that we should refuse to have our own brother-in-law as joint ruler because of his abominable behaviour, and so that we should deny his close kinship, but accept that vile slave [Valens] with him into imperial college".
The peace treaty was finalized at Serdica on 1 March, 317. Whether it was part of the agreement is unknown, but Licinius also had Valens executed.