From the commentary of Hadith Jibril by Hāfiẓ Ibn Ḥajar al-‘Asqalānī:
…The man said: “Messenger of Allah! When is the Final Hour?” The Prophet ﷺ replied: “The one who is questioned about it is no more informed at all than the questioner. However, I shall tell you about its preconditions (ashrāṭihā). When the slave girl gives birth to her master – that is one of its preconditions. And when the naked and barefoot are the top leaders of the people – that is one of its preconditions. And when the shepherds compete in building tall structures – that is one of its preconditions. [It is] among five things none knows but Allah.” [Ṣaḥīḥ Muslim]
“are the top leaders of the people” This means the kings of the earth as explicitly stated in al-Isma‘īlī’s and Abū Farwa’s narrations. Those meant are the people of the desert, as explicitly stated in Sulayman al-Taymī’s and other narrations: “Who are the barefoot and naked?” He replied: “The little Arabs (al-‘urayb).”
Al-Ṭabaranī narrates through Abū Hamza, from Ibn ‘Abbās, from the Prophet ﷺ: “Part of the overthrow (inqilāb) of the Religion is the affectation of eloquence by the boors (al-nabaṭ) and their betaking to palaces in big cities.” Al-Qurṭubī said: “What is meant here is the prediction of a reversal in society whereby the people of the desert will take over and hold sway over every region by force. They will become very rich and their primary concern will be to erect tall buildings and take pride in them. We have witnessed this in our time.” Of identical import are the ḥadīths “The Hour will not rise until the happiest man in the world will be the depraved son of a depraved father (luka‘ ibn luka‘)” and “If leadership is entrusted to those unfit for it, expect the Hour,” both of them in the Ṣaḥīḥ.
[Hāfiẓ Ibn Ḥajar al-‘Asqalānī, فتح الباري شرح صحيح البخاري (Fatḥ al-Bārī Sharḥ Ṣaḥīḥ al-Bukhārī). English translation of excerpts in Sunna Notes Volume 3, Studies in Ḥadīth and Doctrine: The Binding Proof of the Sunna by Shaykh Gibril Fouad Haddad, AQSA Publications, UK, 2010, pp. 159-160, 196]
Ibn Ḥajar al-‘Asqalānī was born in Cairo in 773 H (1372 CE). A Shafi‘i Imam and hadith master (hafiz), he reached the level of Commander of the Faithful in Hadith, the only rank above that of hadith master. He first learned literature and poetry, but then devoted his considerable talents to hadith, which he studied under the renowned African master al-Zayla‘i and others in Cairo, Yemen and the Hijaz. His works were popular in his own lifetime and were hand-copied by the greatest scholars of the era. Known as Sheikh al-Islam, scholars travelled to take knowledge from him, and he was appointed to the judiciary in Egypt several times. He authored a number of works on hadith, history, biography, Koranic exegesis, poetry and Shafi‘i jurisprudence, among the most famous of them his fourteen-volume Fatḥ al-Bārī Sharḥ Ṣaḥīḥ al-Bukhārī [The victory of the Creator: a commentary on the “Sahih” of Bukhari] which few serious students of Islamic knowledge can do without. He died in Cairo in 852 H (1449 CE).
[Excerpted from The Reliance of the Traveller by Shaykh Nuh Keller]