In hoc signo vinces

In hoc signo vinces
"" is a Latin phrase conventionally translated into English as "In this sign thou shalt conquer", often also being translated as "By this sign, conquer".
The Latin phrase itself renders, rather loosely, the Greek phrase "", transliterated as "en toútōi níka", literally meaning "in this, conquer".
History
Lucius Caecilius Firmianus Lactantius was an early Christian author (c. 240 – c. 320) who became an advisor to the first Christian Roman emperor, Constantine I (and tutor to his son), guiding the Emperor's religious policy as it developed during his reign. His work De Mortibus Persecutorum has an apologetic character, but has been treated as a work of history by Christian writers. Here Lactantius preserves the story of Constantine's vision of the Chi Rho before his conversion to Christianity. The full text is found in only one manuscript, which bears the title, Lucii Caecilii liber ad Donatum Confessorem de Mortibus Persecutorum.
The bishop Eusebius of Caesaria, a historian, states that Constantine was marching with his army (Eusebius does not specify the actual location of the event, but it is clearly not in the camp at Rome), when he looked up to the sun and saw a cross of light above it, and with it the Greek words "(ἐν) τούτῳ νίκα" ("In this, conquer"), a phrase often rendered into Latin as in hoc signo vinces ("in this sign, you will conquer").
At first, Constantine did not know the meaning of the apparition, but on the following night, he had a dream in which Christ explained to him that he should use the sign of the cross against his enemies. Eusebius then continues to describe the Labarum, the military standard used by Constantine in his later wars against Licinius, showing the Chi-Rho sign. The accounts by Lactantius and Eusebius, though not entirely consistent, have been connected to the Battle of the Milvian Bridge (312 AD), merging into a popular notion of Constantine seeing the Chi-Rho sign on the evening before the battle.
The phrase appears prominently placed as a motto on a ribbon unfurled with a passion cross to its left, beneath a window over the Scala Regia, adjacent to the equestrian statue of Emperor Constantine, in the Vatican. Emperors and other monarchs, having paid respects to the Pope, descended the Scala Regia, and would observe the light shining down through the window, with the motto, reminiscent of Constantine's vision, and be reminded to follow the Cross.
The Kingdom of Portugal had used this motto since 1139, after the Miracle at the Battle of Ourique, when the first portuguese king D. Afonso Henriques, before his battle against the moorish King Ali ibn Yusuf, experienced a similar miracle to Constantine's. The miracle was later famously retold through the written epic poem the Lusíadas.
Cultural references
Inscribed on the banner of the Sanfedismo in 1799
Inscribed in Greek on the flag (obverse side) of the Sacred Band of the Greek War of Independence
Part of the trademark for Pall Mall cigarettes. "PALL MALL IN HOC SIGNO VINCES 'WHEREVER PARTICULAR PEOPLE CONGREGATE'"
It is the public motto of the English Defence League, emblazoned around the group's logo.
The phrase is the motto on some Byzantine coins (e.g. the folles of Constans II).
It is the motto on most regimental flags of the Irish Brigade (France).
In hoc signo vinces was the motto of the Sherbrooke Regiment, which is perpetuated by the Sherbrooke Hussars, a Canadian reserve regiment
In hoc signo vinces is the motto on the O'Donnell coat of arms.
It is the motto of the College of the Holy Cross in Worcester, Massachusetts.
It is the official motto of the Knights Templar in the American York Rite of Freemasonry.
It is the motto of the Regimiento de Caballería «Montesa» n.º 3 of the Spanish Army.
See also
List of Latin phrases
Citations
General and cited sources
At the Internet Archive.
External links
312
Christian terminology
Constantine the Great and Christianity
Eusebius
Latin mottos
Latin religious words and phrases