May 28. On this date in 1953, Shoghi Effendi sent a cablegram "to The Bahá'í World" wherein he first referred to the "Knights" of Bahá'u'lláh, calling for the "dispersal, immediate, determined, sustained and universal" of pioneers "throughout the unopened territories of the planet". He announced his intention to inscribe, in chronological order, the names of the "spiritual conquerors" on an illuminated "Roll of Honor, to be deposited at the entrance door of the inner sanctuary of the Tomb of Bahá'u'lláh, as a permanent memorial of the contribution by the champions of His Faith at the victorious conclusion of the opening campaign of the Global Crusade..."

May 28. On this date in 1953, Shoghi Effendi sent a cablegram "to The Bahá'í World" wherein he first referred to the "Knights" of Bahá'u'lláh, calling for the "dispersal, immediate, determined, sustained and universal" of pioneers "throughout the unopened territories of the planet". He announced his intention to inscribe, in chronological order, the names of the "spiritual conquerors" on an illuminated "Roll of Honor, to be deposited at the entrance door of the inner sanctuary of the Tomb of Bahá'u'lláh, as a permanent memorial of the contribution by the champions of His Faith at the victorious conclusion of the opening campaign of the Global Crusade..."

The Paramount Issue
On occasion of the sixty-first Anniversary of the Ascension of Bahá'u'lláh, on the morrow of the opening, initial phase of the momentous World Crusade, call upon His followers in all continents to allow no slackening, nay, to insure acceleration of the marvelous momentum generated by the historic celebrations climaxing the festivities of Holy Year. The dispersal, immediate, determined, sustained and universal, throughout the unopened territories of the planet, is the paramount issue challenging the spirit and resources of the privileged prosecutors of the Ten-Year Plan in the course of the current year.
All National Assemblies are urged to give it priority assignments in their national budgets. The chief executors of 'Abdu'l-Bahá's Plan, by virtue of the primacy conferred in His Tablets, are accorded the prerogative to stimulate the vital process of the dispersal through the dispatch, in addition to their allotted tasks, of pioneers to the virgin territories allocated to their sister communities East and West.
Once again I appeal to members of all communities to arise and enlist, ere the present opportunity is irretrievably lost, in the army of Bahá'u'lláh's crusaders. The hour is ripe to disencumber themselves of worldly vanities, to mount the steed of steadfastness, unfurl the banner of renunciation, don the armor of utter consecration to God's Cause, gird themselves with the girdle of a chaste and holy life, unsheathe the sword of Bahá'u'lláh's utterance, buckle on the shield of His love, carry as sole provision implicit trust in His promise, flee their homelands, and scatter far and wide to capture the unsurrendered territories of the entire planet.
Would to God that Bahá'í warriors, six score and ten, the number required to fill the gaps in the still unconquered territories of the globe, will promptly arise and enroll themselves to achieve the goals ere the conclusion of the opening year of the decade-long, greatest collective enterprise since the memorable episodes associated with the Dawn-Breakers of the Heroic Age.
Planning to inscribe, in chronological order, the names of the spiritual conquerors on an illuminated Roll of Honor, to be deposited at the entrance door of the inner Sanctuary of the Tomb of Bahá'u'lláh, as a permanent memorial of the contribution by the champions of His Faith at the victorious conclusion of the opening campaign of the Global Crusade which is destined to attain consummation at the Most Great Jubilee commemorating the Centenary of the Declaration of His Mission. Anticipate making periodic announcements of the names of the valiant knights upon their arrival at their posts to discharge their historic missions.
Share message National Assemblies of the Bahá'í World.
--Shoghi
[Cablegram, May 28, 1953]

What has always struck me about the designation of Knights of Bahá'u'lláh is the arbitrariness with which the "virgin territories" were defined. For example, the Cook Islands and Tonga Island, both part of the Realm of New Zealand have distinct sets of Knights, while Niue and the Chatham Islands, also part of the Realm of New Zealand, are Knightless.
 
Several islands off the coast of Alaska have distinct Knights, like Baranof Island , Kodiak Island, and the Aleutian Islands. Yet other Alaskan islands, like the Pribilof Islands are Knightless.
The Brazilian state of Amapá has its own Knights (for Portuguese Guiana), while the other Brazilian states are Knightless.

Crete and Rhodes have Knights distinct from the Knights of mainland Greece, yet other Greek islands, like Santorini and Samos, are Knightless.

Key West has its own Knight, yet the other Florida Keys are Knightless.

Tiny islands, like Great Manan, have their own Knights. St. Thomas Island has its own Knight, yet the remaining Leeward Islands have one set of Knights, representing numerous politically and geographically independent islands. Similarly, the Windward Islands have one set of Knights, representing numerous politically and geographically independent islands.