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Chi-Rho

The Chi-Rho, the monogram of Christ formed from the first two Greek letters of his title: its link with the emperor Constantine, its use in early Christian art and where you see it today.

Also called Christogram · Labarum · Sacred monogram

In brief

  1. I.The Chi-Rho joins the Greek letters chi (X) and rho (P), the first two letters of Christos, “Christ”.
  2. II.It is linked with Constantine, who is said to have put it on his soldiers’ shields before the battle of the Milvian Bridge in 312.
  3. III.It was one of the most common Christian signs of the 4th and 5th centuries.
  4. IV.It is still used on church vestments, altars and in decoration.

Chapter I

What it means

The Chi-Rho is a monogram: two letters set one over the other to stand for a name. Chi and rho begin Christos, the Greek translation of the Hebrew Messiah, “anointed one”. To show the monogram was to proclaim Jesus as the Christ.

Under Constantine it also became a sign of victory, the emblem under which the emperor believed God had given him triumph.

Chapter II

Where it comes from

The Christian writer Lactantius reports that Constantine, before his battle against his rival Maxentius at the Milvian Bridge in 312, was told in a dream to mark the heavenly sign on his soldiers’ shields. Eusebius tells of a vision of a sign in the sky with the words “In this sign, conquer”. Constantine won, and the Chi-Rho appeared on his coins and standards.

Through the 4th and 5th centuries it was carved on sarcophagi, set in mosaics and pressed into lamps and rings across the Roman world.

Chapter III

Where you see it today

The Chi-Rho is embroidered on priests’ vestments and altar cloths, carved on churches and used in Christian design. The magnificent Chi-Rho page of the Book of Kells, an Irish gospel book of about 800, is one of the most famous pages in medieval art.

Questions people ask

What do the alpha and omega beside it mean?

The first and last letters of the Greek alphabet. In the Book of Revelation Christ says, “I am the Alpha and the Omega”, the beginning and the end.

What was the labarum?

The military standard Constantine adopted, topped by the Chi-Rho. The word is often used for the monogram itself.

Sources and further reading

  1. Encyclopaedia Britannica, “Sacred monogram”
  2. Encyclopaedia Britannica, “The Battle of the Milvian Bridge”
  3. Robin M. Jensen, The Cross: History, Art, and Controversy (Harvard University Press, 2017)
  4. Encyclopaedia Britannica, “Religious symbolism and iconography”

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