The "Crimson Ark" refers to the Cause of Bahá’u’lláh. His followers are designated as the "companions of the Crimson Ark", lauded by the Báb in the Qayyúmu’l-Asmá.
116. O Emperor of Austria! He Who is the Dayspring of God’s Light dwelt in the prison of Akká at the time when thou didst set forth to visit the Aqsá Mosque. [#85]
Francis Joseph (Franz Josef, 1830-1916), Emperor of Austria and King of Hungary, made a pilgrimage to Jerusalem in 1869. While in the Holy Land he failed to take the opportunity to inquire about Bahá’u’lláh Who at that time was a prisoner in Akká (Acre).
The Aqsá Mosque, literally, the "Most Distant" Mosque, is referred to in the Qur’án, and has become identified with the Temple Mount in Jerusalem.
117. O King of Berlin! [#86]
Kaiser William I (Wilhelm Friedrich Ludwig, 1797-1888), the seventh king of Prussia, was acclaimed first Emperor of Germany in January 1871 at Versailles in France, following the victory of Germany over France in the Franco-Prussian War.