The Chi-Rho symbol is one of the earliest Christograms and has been an important Christian symbol since the days of Constantine the Great. Chi and Rho are the first two letters of the Greek word ΧΡΙΣΤΟΣ, which means “Christ.”
The Chi-Rho emblem was used by the Roman Emperor Constantine I (r. 306–337) as part of a military standard (vexillum). Constantine’s standard was known as the Labarum. Early symbols similar to the Chi Rho were the Staurogram and IX monogram. They were used by early Christians as code language and secret symbols during the persecution of Christians in the Roman Empire. When Constantine became sole ruler of the empire, he made Christianity legal with the Edict of Milan in 313. The beginnings of Christendom emerged during Constantine’s reign.
There are various accounts of Constantine’s conversion to Christianity, but they all agree that before the Battle of the Milvian Bridge in 312, Constantine had a vision of Christ assuring him of victory if he fought under the protection of the Christian God. The accounts differ as to whether Christ gave him a physical sign. One version says that the sign was the Chi-Rho, a Christogram formed from the first two letters of the Greek word ΧΡΙΣΤΟΣ (Christos). Another says the sign was a cross in the sky with the words “Εν Τούτῳ Νίκα” (“By this, conquer” in Greek).
After Constantine’s vision and victory at the Milvian Bridge, Constantine had the Chi-Rho emblem painted on his soldiers’ shields, and thereafter the emblem was shown on imperial items, such as the emperor’s labarum and coins. The emperor’s continued military successes confirmed for Constantine that the Chi-Rho symbol was under divine protection. Constantine’s sons and succeeding Christian emperors would use the symbol as part of their own military standards.
Thus, the Chi-Rho became an imperial emblem of the Roman Empire. It continued as such after the reign of Constantine, although the Labarum was later destroyed. Under Constantine’s successors, Christian usage of the Chi-Rho became more widespread and more overt. After Constantine, the symbol was widely used by Christians as a vexillum (military standard) and as a Christogram. Its use spread into the Caucasus and the Germanic peoples. The Chi-Rho symbol continues to be used today by some Christian denominations, fraternal organizations, and sororities and fraternities.
Meaning and Origins
The Chi-Rho is a Christogram that brings together the first two letters of the Greek word for Christ, ΧΡΙΣΤΟΣ (Christos). This ancient symbol fuses the Greek letters chi (Χ) and rho (Ρ).
In Greek numerology, chi has a value of 600 and rho has a value of 100. The combined total of 700 corresponds to the seven gifts of the Holy Spirit: wisdom, understanding, counsel, fortitude, knowledge, piety, and fear of the Lord. The Chi-Rho represents Jesus due to the numeric connection to Christ’s character and identity. The seven gifts are mentioned by the prophet Isaiah (Isaiah 11:2).
The Chi-Rho is also connected to the crucifixion of Jesus, as chi and rho are the first two letters of the word Christos – Christ. In this sense, the blending of chi and rho represents the death (cross of crucifixion) and resurrection of Jesus, a central tenet of the Christian faith.
Earliest images of the Chi-Rho emblem date to the early 4th century during the reign of Constantine. It was part of Constantine’s new military standard, the labarum. But some scholars suggest the origins of the symbol may predate Constantine and associate it with Christian artifacts dating back to the period of Roman persecution. Some of these artifacts use the Chi-Rho more covertly.
Before Constantine legalized Christianity in the Roman Empire, early Christians used the Chi-Rho as a secret symbol to covertly identify their community. Two similar Christograms are the IX monogram which uses the initials of Jesus Christ in Greek, and the Staurogram which superimposes a cross over the rho to depict crucifixion.
Use by Constantine
The Roman Emperor Constantine I adopted the Chi-Rho symbol when he had a vision before the pivotal Battle of the Milvian Bridge in 312 AD. Having received instructions in a dream to paint the heavenly sign on his soldiers’ shields, Constantine defeated his rival Maxentius and consolidated his hold on the Roman Empire. This proved to be a turning point for Christianity, as Constantine made the faith legal shortly thereafter with the Edict of Milan (313 AD).
There are different accounts as to what exactly Constantine saw in his vision. Greek author Eusebius of Caesarea wrote that Constantine saw a cross of light in the sky above the sun with the words “Εν Τούτῳ Νίκα” (“By this, conquer” in Greek) emblazoned next to it. In this version of the vision, Christ then appeared to Constantine in a dream to instruct him to make a likeness of the symbol he saw as protection in battle.
A later Latin narrative claims the Chi-Rho appeared to Constantine, with Christ telling him to mark his soldiers’ shields with the Christogram. While the two accounts differ, both have the Chi-Rho as the central part of Constantine’s vision and subsequent victory.
After the battle, Constantine had the Chi-Rho painted on his own shield and the shields of his soldiers. He made the Christian God the patron of his army, and devoted the empire to the Christian faith. The Emperor told his biographer Eusebius of Caesarea that the Chi-Rho symbol helped convince him of the reality of Christ’s power.
Constantine went on to decisively consolidate power as sole emperor, attributing his military victories to the protection of the Christian God. His legalization of Christianity transformed the Roman Empire and European history. The emperor’s continued successes with the Chi-Rho on imperial standards convinced him that the symbol had power and that he was favored by the Christian God.
While Constantine later shifted favor to the symbol of the cross, the Chi-Rho remained part of imperial symbolism for centuries after his reign. It was emblazoned on imperial labarums and coins.
Later Usage and Significance
After Constantine, the Chi-Rho continued in use and increased in popularity especially in the eastern part of the Roman empire. It was embraced by the emperor as an imperial emblem, but also widely adopted by regular Christians as a symbol for their faith.
As Christianity gained ascendancy in the Roman world, use of the Chi-Rho became more overt. The symbol adorned Christian tombs and catacombs at least from the 4th century, and was used to mark Christian objects and people. As Christograms like the Chi-Rho embodied the first two letters of Christ’s name, they were considered holy symbols with divine power.
Various inscriptions use the Chi-Rho symbol, including the phrase “ΧΡ” alone. The symbol continues to decorate religious art and architecture around the world today. Some examples are the Bonn Cross at the largest Roman Catholic church in Germany, and decorations at Westminster Cathedral in London.
After the fall of Rome, the Chi-Rho was used by Germanic tribes that adopted Christianity, such as the Ostrogoths, Visigoths, and the Burgundians. In insular art, the Chi-Rho appeared in metalwork, carvings and illuminated bibles or psalters such as the Book of Kells and Book of Durrow. Saint Patrick famously incorporated the Chi-Rho along with other Christograms into an Irish Celtic Cross to appeal to pagans. His use demonstrates how it could represent Christianity to cultures unfamiliar with the Latin alphabet.
During the European Renaissance and Protestant Reformation, the Chi-Rho was used as a symbol identifying Christ. Many Protestant churches use the Chi-Rho in stained glass windows, carvings and priestly vestments. Examples can be seen in cathedrals and churches across Europe as well as in North and South America.
Among Catholic and Orthodox Christians, the Chi-Rho continues to be venerated as a symbol for Christ. It is found on vestments, sacred vessels, and frescoes. In Catholicism, the Chi-Rho adorns mitres worn by popes and bishops as well as croziers used by bishops. The symbol is also connected to abbots as successors of Saint Peter because of the meaning associated with the Greek letters.
Modern Usage
While Constantine’s Chi-Rho formed an important symbolic connection between early Christianity and the Roman Empire, the Christogram has continued to be used in the modern era across various contexts.
The symbol appears today in Christian religious iconography, church architecture, vestments, funerary monuments, and the seals or insignia of religious orders. Some denominations and fraternal organizations also incorporate the Chi-Rho into their imagery.
For example, Eastern Orthodox churches display the Chi-Rho prominently on vestments as well as on analogia and antimension altar cloths. It represents the incarnation of Christ and his authority. In Orthodox tradition, the zig-zag Rho represents the electric spark of life and Resurrection from the tomb.
The Lutheran Church Missouri Synod in North America uses a Chi-Rho symbol set inside an oval, with a cross at the base. This is the corporate seal for the church body as well as its official insignia. The emblem appears on churches, publications, vestments, and other LCMS art.
Among Catholics, Pope Benedict XVI used a papal ferula featuring the Chi-Rho. Pope Francis had a Chi-Rho placed on his crozier as a bishop that he continues to use in his papacy. The symbol also appears on mitres worn by Catholic leaders. And it is connected to the world of Catholic education. The Chi-Rho was chosen as motto and emblem of the Catholic fraternal order Knights of Columbus, founded in 1882.
Outside of explicitly religious contexts, the Chi-Rho has also been used in heraldic emblems, especially in Orthodox countries. It appears in Greek coats of arms and family seals. Many fraternities and sororities use the symbol, especially in colleges with religious affiliations. The Chi-Rho as iconography thus continues to represent concepts like honor, christian values, victory and commitment.
While originating in a Roman and Christian context, the Chi-Rho beyond that heritage represents conquest, power, and divine blessing. The Victor Constantine experienced at the Milvian Bridge established the symbol’s protective power in the minds of its Christian inheritors. The dual meanings of death and resurrection in its encapsulation of “Christ” offer a message of hope and overcoming.