See History of Information.

Two hours and eleven minutes after sunset Siyyid `Alí-Muhammad made His declaration to Mullá Husayn-i-Bushrú'í in the upper room of His House. [DB52-65]

"I am, I am, I am, the promised One! I am the One whose name you have for a thousand years invoked, at whose mention you have risen, whose advent you have longed to witness, and the hour of whose Revelation you have prayed God to hasten. Verily I say, it is incumbent upon the peoples of both the East and the West to obey My word and to pledge allegiance to My person." [DB315-316]

To set the context, this came during the period known as "Tanzimat" (lit. Reorganization) 1838 to 1876. The Tanzimat era was characterised by various attempts to modernise the Ottoman Empire and to secure its territorial integrity against internal nationalist movements and external aggressive powers. The reforms encouraged Ottomanism among the diverse ethnic groups of the Empire and attempted to stem the tide of the rise of nationalism in the Ottoman Empire. During the Tanzimat period, the government's series of constitutional reforms led to a fairly modern conscripted army, banking system reforms, the decriminalization of homosexuality, the replacement of religious law with secular law and guilds with modern factories. The Ottoman Ministry of Post was established in Istanbul in 1840. [Wikipedia]

The fulfillment of the prophecies of Christ and of the Bible has been over a period of a hundred years or more matter of common knowledge and remark in the West. But the full extent of that fulfillment is only seen in Bahá'u'lláh. The proclamation of His Faith was made in 1844, the year when the strict exclusion of the Jews from their own land enforced by the Muslims for some twelve centuries was at last relaxed by the Edict of Toleration and "the times of the Gentiles" were "fulfilled." [GPBiv Introduction by George Townshend]