I think you're thinking of Sol invuctus, which is translated as "Unconquered Sun." There was a cult for this sun deity formed by the emperor Aurelius in the latter days of the Roman religion. The term appeared on Roman coinage through the reign of Constantine, but removed after his conversion to Christianity.
The epithet Invictus was applied to many Roman deities,and the family of Aruelius was known to be participants in the ancient cult of Sol, the original sun deity for the Latins and Estruscans (the equivalent to the Greek Helios).
The name you mentioned "Order of the Victorious Sun" sounds like someone applied some creative license. I'm unfamiliar with any reference to it.
If you are referring to Constantine I (or the Great), his full name was Flavius Valerius Aurelius Constantinus Augustus. Augustus was the title of the emperors.
Constantine the great's full name in Latin was Flavius Valerius Aurelius Constantinus Augustus.
Julius CeasarFlavius Valerius Aurelius Constantinus
Flavius Valerius Aurelius Constantinus Augustus was found Constantinople as the new capital of the roman empire. Constantine chooses Byzantium as the new capital of the Empire and renames it Constantinopolis.
Flavius Valerius Constantinus at Naissus (in modern Yugoslavia), Constantine was the son of Constantius Chlorus and his concubine Helena.
He was a Roman emperor but he mostly governed the Eastern half of the empire
'Constantine the Great''Saint Constantine'Flavius Valerius Constantinus(AD ca. 285 - AD 337)
Caesar Flavius Valerius Aurelius Constantinus Augustus(he has a long name), the first Christian Emperor of Rome, brought relief to Christians by reversing the persecutions of his predecessor, Diocletian, and issued (with his co-emperor Licinius) the Edict of Milan in 313, which proclaimed religious tolerance throughout the empire.
Flavius Valerius Aurelius Constantinus Augustus Born: 272 died 337. He was from 306 to 337 AD a Roman Emperor.He was a general of an army who fought against various tribes around the Roman Empire, and defeated other emperors, Maxentius and Licinius during civil wars.He decreed the "Edict of Milan" in 313, which declared religious tolerance of all religions in the empire. This ended almost 300 years of Christian persecution. Due to this and other activities in support of the Christian Church, he was named a saint.Constantine established an imperial residence at Constantinople, which would become the capital of the Eastern Roman Empire for over a thousand years. He is often considered the first in the line of Byzantine emperors.
The Emperor Constantine I (He died in 337, so it could also be his succsesor); weather he converted whole hearted or just to appease the growing number of Christian Romans is still being debated. "Flavius Valerius Aurelius Constantinus[2] (27 February ca. 272[1] - 22 May 337).....Best known for being the first Christian Roman Emperor...........the Edict of Milan in 313." Wikipedia page: http://en.wikipedia.org/wiki/Constantine_I_(emperor)
Valerius of Trèves died in 320.
Valerius Herberger died in 1627.