The work of the Order was now sufficiently well known to attract the support of the Royal Family and, in 1876, the Princess of Wales (later Queen Alexandra), accepted membership as a dame of Justice. Both the Dukes of Albany and Connaught, two of the Queen's younger sons, became knights of Justice, the latter being a particularly enthusiastic supporter of the Order. The Prince of Wales himself had accepted the dignity of Bailiff Grand Cross of Honor and Devotion of the Sovereign Military Order in 1881, demonstrating his enthusiasm for chivalric organizations.[1] In 1888 the Prince presented a petition to the Queen, on behalf of the Prior and members of the English Order of Saint John, that she would grant them her Royal Charter, thus regulating the Order's legal position in Great Britain. This petition received the Royal Assent on 14 May of that year and the Order was given the style of the "Grand Priory of the Order of the Hospital of Saint John of Jerusalem in England" with the Queen as Sovereign Head[2] and the Prince of Wales himself as Grand Prior.

Although not a State Order, the Order of Saint John was now an Order of the British Crown, its decorations could be worn on military uniform and announcements of appointments or promotions made in the official government periodical, the London Gazette. However the rank of "knight" of the Order did not (and still does not) confer the title of "Sir" on the recipient and members of the Order of Saint John are not given any special precedence. New knights of the Order receive the accolade from the Grand Prior when they are touched on the shoulder with a sword and receive their robes and insignia.

The Prince of Wales succeeded Manchester as Grand Prior by virtue of the Royal Charter of 1888 and his eldest son, the Duke of Clarence, became Sub-Prior (until his death in 1892 when his younger brother the Duke of York succeeded him). With the death of Queen Victoria in 1901 the Prince of Wales succeeded, as Edward VII, and the Duke of York became Prince of Wales and Grand Prior. The latter's successor as Sub-Prior was no longer a member of the Royal Family and, between 1901 and 1948, when the title of Lord Prior was instituted for the 2nd Lord Wakehurst, there were six peers appointed to this charge. With the accession of George V in 1910, the new King appointed his uncle, H.R.H. the Duke of Connaught (Bailiff of Egle since 1894), as Grand Prior. Connaught was succeeded in 1939 by H.R.H. Prince Henry, Duke of Gloucester (younger brother of King George VI), who was himself succeeded by his son, H.R.H. Prince Richard, Duke of Gloucester, the present Grand Prior, in 1974. Although the establishment of the British Grand Priory was unrecognized by the Order of Malta, Queen Victoria's Charter stated that it was the "Sixth or English Language of the Most Venerable Order of the Hospital of Saint John of Jerusalem" and a relationship with the Bailiwick of Brandenburg was established immediately with the appointment of Prince Albert of Prussia, the Herrenmeister of the Johanniter Order, as an honorary knight of Justice.

In 1907 the Grand Prior was empowered by a further Royal Charter to found Priories throughout the British Empire, since the Ambulance Brigade was already becoming established across the globe. In 1918 the Priory for Wales was founded as a separate entity, the Priory of Scotland was given autonomous status in 1947, and branches of the Order were established as the Priory for South Africa (with approximately eight hundred members today), the Priory in New Zealand (with nearly seven hundred members), the Priory of Canada (with approximately six thousand four hundred members), the Priory in Australia and the Commandery of Western Australia (with nearly one thousand five hundred members together), the Commandery of Ards in Northern Ireland was made self-governing in 1952, and the Commandery in Central Africa. Today the world-wide membership of the Order (fifty-eight per cent of whom are serving brothers or sisters) totals approximately twenty-five thousand. Priories are headed by a Prior (the Governor-General in states of which the British Sovereign is also Sovereign where Priories are established), Commanderies by a Knight Commander (this is not longer a rank in the Order but an executive post, held by a Knight pro tempore).
[1] He was the first and only member of the British Royal Family ever to receive a distinction or membership from the Sovereign Military Order.
[2] The title of Sovereign Head is similar to the title that the British Monarch holds as Sovereign (without the addition of the word "Head") of the other British Orders, while a junior member of the Royal Family is Grand Prior, just as junior members of the Royal Family hold the titles of Grand Master of the Orders of the Bath, Saint Michael and Saint George, the British Empire and the Royal Victorian Order
page I
The first members of the Order in North America were William Winthrop (Honorary U.S. Consul in Malta), Colonel John T. Heard of a famous Boston family (who was appointed a member of the Capitular Commission representing North America in 1862), and Colonel John Winthrop of Louisiana (all listed as members in the 1864 Roll). A small number of American members continued to be admitted until permission was given for the formation of the American Society in 1958 and the further expansion of the membership in the United States. In 2002 the Society was succeeded by the Priory of the United States that has just over one thousand and fifty members, from serving brother and sister to knight or dame. It is governed by the Prior (presently John R. Drexel IV) [3], assisted by the Chancellor and Council. Permission has been given for the decorations of the Order to be worn on U.S. military uniform.

In Canada the Most Venerable Order has been given responsibility for running the principal ambulance services of the Dominion. There are more than eleven thousand uniformed Brigade volunteers and, in the Association, twelve thousand non-uniformed volunteers and nine thousand two hundred and fifty nationally certified instructors with two hundred and ninety-four permanent salaried staff members. Saint John Canada has been most effective, providing first aid and cardiopulmonary resuscitation training to more than four hundred and sixty thousand Canadians in 1989 alone. The Canadian Priory itself has six thousand six hundred and forty members (as of 1 January 1990), of whom there are two members of the first class (one Bailiff and one dame grand cross), thirty-eight knights of Justice, one hundred and eighty-four knights and dames of Grace, four hundred and twenty-two commanders, eight hundred and seventy-five officers and four thousand nine hundred serving brothers and sisters. The Commandery of Canada was established in 1934 and raised to a Priory in 1946; the Governor-General of Canada has always been the Prior of Canada (although this is not a statutory requirement). Executive responsibility for the conduct of the affairs of the Priory is delegated by the Prior to the Chancellor, or, on certain occasions, to one of the executive officers. The Priory has Councils in each of the Provinces, the Northwest Territories and the National Capital Region.

Elsewhere there is a Saint John presence in some forty countries including active Saint John Associations in several non-Christian countries, most notably Malaysia which now has some sixty-thousand volunteer members.
[3] Whose mother, the Hon Noreen Drexel, née Stonor, was the daughter of Lord Camoys, one of England's most distinguished recusant families.
page II