[1] The apostles were designated as such by Shoghi Effendi, head of the religion in the earlier half of the 20th century, and the list was included in The Baháʼí World, Vol.
[2] These individuals played a vital role in the development of the Baháʼí Faith, consolidating its adherents and bringing its teachings around the world.
To Baháʼís, they filled a similar role as the sons of Jacob, the apostles of Jesus, Muhammad's companions, or the Báb's Letters of the Living.
He outlines certain conditions for this attainment, namely firmness in the Covenant of God, fellowship and love amongst the believers, and continually travelling to all parts of the continent, "nay, rather, to all parts of the world".
[6] Shoghi Effendi referred to Martha Root as "that unique and great-hearted apostle of Baháʼu'lláh", but she is not considered one of the nineteen Apostles designated as such by Shoghi Effendi.