Red Cross of Constantine
is an invitational body . There are also two chair degrees conferred on the Viceroy and Sovereign of a Conclave, and two honorary orders: Knight Commander of Constantine and Knight Grand Cross. The governing body of the Order for the United States of America and Its Jurisdiction is styled The United Grand Imperial Council of Knights of the Red Cross of Constantine and Appendant Orders for the United States of America and Its Jurisdiction.

Officially known as the The Masonic and Military Order of the Red Cross of Constantine and the Orders of the Holy Sepulchre and St. John the Evangelist (the latter two of which are called the Appendant Orders) the Red Cross of Constantine is an invitational body open to Royal Arch Masons with a subscribed belief in "the Christian religion as revealed in the New Testament".
The purpose of the Constantinian Orders are to commemorate the first elevation of Christianity from the position of a despised and proscribed heresy to that of a legally recognized and honored religion, to cultivate the social virtues, appeal to the intellectual and moral qualities, preserve as far as possible the customs of the fraternity and bring about good fellowship and understanding between all branches of Masonry.
Members are styled Knight Companions meeting in local Conclaves.
Conclaves confer the first degree, Knight of the Red Cross of Constantine, while the two Appendant Orders are under the control of the Regional Conclaves. This degree is short, but lays the foundation of the order and the story of the Roman Emperor Constantine and the Battle of Milvian Bridge.
The Order of the Holy Sepulchre is the first of the Appendant Orders and surrounds the legend of the guards who guarded the supposed place where Jesus Christ was buried. This degree is conferred with a Sanctuary and the presiding officer is known as a Prelate.
The second Appendant Order is known as the Order of St. John the Evangelist. In comparison to the first Appendant Order, this degree is relatively short. This degree is conferred in a Commandery and the presiding officer is known as Commander.
There are also two chair degrees conferred on the Viceroy and Puissant Sovereign of a Conclave, and two honorary orders: Knight Commander of Constantine and Knight Grand Cross.
The degree of Venerable Priest-Masons, or Installed Eusebius, is conferred upon those Knight Companions elected as Eminent Viceroy (the second in command of a Conclave) . The degree is conferred in a College of Priest-Masons. The ceremony is highly spiritual in nature, and incorporates more overtly religious symbolism and ritual. Having received this degree the Installed Eusebius or Priest-Mason is entitled to serve as Viceroy in his own, or any other, Conclave or College. In general this degree may only be conferred on those elected to serve as Viceroy of a Conclave, although exceptions are possible by dispensation.
For those elected to serve as Puissant Sovereign (the leader of a Conclave), a Knight Companion is to be admitted to the degree of Perfect Prince-Mason which is conferred in a Senate of Princes-Mason.
The United Grand Imperial Council of Knights of the Red Cross of Constantine and Appendant Orders for the United States of America and Its Jurisdictions, except the State of Maine.
The first American Conclave was United States Premier Conclave No 38 at Washington, Pennsylvania (now Conclave No 1 in America). However, the records of the English Grand Conclave show warrant No 38 applying to St James' Conclave at Maitland, in Canada. Both sources agree that it was consecrated on 14 December 1870.
In 1871 and 1872 a large number of Conclaves were consecrated in Pennsylvania, Illinois, and New York, and during 1872 sovereign Grand Imperial Councils were founded in all three States, starting with Pennsylvania on 14 June 1872. In the following three years, Grand Imperial Conclaves were established in the states of Massachusetts, Michigan, Kentucky, Indiana, Vermont, Maine and New Jersey. In 1907 most of the individual jurisdictions were united into the GIC of the United States of America, and in 1946 the name was changed to reflect the operation of Conclaves in Mexico and the Philippines.
In 1894, the Grand Imperial Council of Pennsylvania had withdrawn from the Union and established a rival jurisdiction. The two rival authorities, having long co-existed, entered into dialogue in the 1950s, and were reconciled and reunited on 18 February 1958, into the single jurisdiction for almost the whole of the United States.
The Red Cross Masons of Maine have chosen to maintain their independence, with their own Grand Imperial Council. The State of Vermont also had its own independent Grand Imperial Council until 1997; in that year Vermont voted to close its independent body, and to be incorporated into the United GIC.