1927 -- First time delegates from nine leading provinces of Persia convened a conference

With their traditional fidelity and characteristic vigor, notwithstanding the unimaginable hindrances they have to face, they have convened their first historic representative conference of various delegates from the nine leading provinces of Persia, have evolved plans for holding every year as fully representative a convention of Bahá'í delegates in Persia as circumstances permit, and modelled after the method pursued by their brethren in the United States and Canada. 
(Letter written by Shoghi Effendi, dated October 18, 1927; printed in 'Baha'i Administration')

Nov. 27, 1924 -- The Guardian approved suggestion by Horace Holley to create Baha’i Year Books

The suggestion made by my dear and able friend, Mr. Horace Holley, as to the compilation of an annual " Bahá'í Year Book" is extremely valuable and timely. I am much impressed by it, and feel that an immediate start should be made. I believe it can best be now undertaken under the direction and supervision of your Assembly until the time should come for the friends in the East and particularly Persia to participate effectually in its development. I trust you will send me a copy of the skeleton of the material you propose to include, and I shall here attempt to fill up any gap and render any assistance I can to make it as comprehensive, as attractive, and as authoritative as possible. (Shoghi Effendi, 'Baha'i Administration')

Circa May 1922 – Shoghi Effendi left for a time the affairs of the Cause both at home and abroad in the hands of Bahiyyih Khanum

In the Name of God

This servant, after that grievous event and great calamity, the ascension of His Holiness 'Abdu'l-Bahá to the Abha Kingdom, has been so stricken with grief and pain and so entangled in the troubles (created) by the enemies of the Cause of God, that I consider that my presence here, at such a time and in such an atmosphere, is not in accordance with the fulfilment of my important and sacred duties.

For this reason, unable to do otherwise, I have left for a time the affairs of the Cause both at home and abroad, under the supervision of the Holy Family and the headship of the Greatest Holy Leaf [Bahiyyih Khanum, sister of 'Abdu'l-Bahá] until, by the Grace of God, having gained health, strength, self-confidence and spiritual energy, and having taken into my hands, in accordance with my aim and desire, entirely and regularly the work of service I shall attain to my utmost spiritual hope and aspiration.

The servant of His Threshold,

Shoghi

Haifa, Palestine.
Circa May, 1922 (undated).

(Shoghi Effendi, 'Baha'i Administration')

September 1867-August 1868: the most momentous Tablet of Baha’u’llah, The Suriy-i-Mulúk (the Surih of the Kings) was revealed in Adrianople

The first full translation of this Tablet is included in the Summons of the Lord of Hosts. In the Introduction section of that book the Universal House of Justice explains that:

Included in this collection, as well, is the first full translation of the Súriy-i-Mulúk or Súrih of the Kings, which Shoghi Effendi described as “the most momentous Tablet revealed by Bahá’u’lláh in which He, for the first time, directs His words collectively to the entire company of the monarchs of East and West”. It sets forth both the character of His mission and the standard of justice that must govern the exercise of their rule in this Day of God:

“Lay not aside the fear of God, O kings of the earth, and beware that ye transgress not the bounds which the Almighty hath fixed. Observe the injunctions laid upon you in His Book, and take good heed not to overstep their limits. Be vigilant, that ye may not do injustice to anyone, be it to the iii extent of a grain of mustard seed. Tread ye the path of justice, for this, verily, is the straight path.” (Baha’u’llah)

The Tablet introduces some of the great themes that were to figure prominently in the Writings of Bahá’u’lláh over the next two and a half decades: the obligation of those into whose hands God has entrusted civil authority to institute the reign of justice, the necessity for the reduction of armaments and the resolution of conflicts among nations, and an end to the excessive expenditures that were impoverishing these rulers’ subjects.

Baha’i Summer Schools Originated in America

The Bahá'í summer schools were originated in America to meet the requirements of the friends. They have been adopted by other Bahá'í Communities the world over, but there is no reason why they should be called "summer schools". There is nothing rigid about the term, it is purely descriptive. 
(From a letter dated 26 December 1941 written on behalf of Shoghi Effendi to the National Spiritual Assembly of Australia and New Zealand; The Compilation of Compilations vol. 1)

Amazing growth with respect to the administrative order of the Faith

In 1953 there were only 12 National Spiritual Assemblies.

In Ridvan 1964, there were 69 National Spiritual Assemblies!!

In 1953 there were “slightly more than six hundred Local Spiritual Assemblies, the greater part of which were situated in Persia, North America and Europe ..”

In Ridvan 1964, there were “nearly four thousand six hundred Local Spiritual Assemblies scattered throughout the continents and islands of the world.”!! (Adapted from the 1964 Ridvan message of the Universal House of Justice)