He was born in the Keserwan area of Mount Lebanon to a long line of clerks serving the Shihab emirs and other local chieftains.
Tannus was taught Arabic and Syriac grammar and throughout his career serving the Shihab emirs and as a merchant, he pursued education in the fields of medicine, jurisprudence, logic, ethics, natural sciences, Turkish and Italian.
[3] Members of the family served as teachers and clerks for the Muslim, Christian and Druze nobility of Mount Lebanon and its environs from the early 17th century.
Tannus's father succeeded Mansur and later served the Shihab emir Hasan ibn Umar, who moved him back to the Shidyaq ancestral village of Ashqout in Keserwan.
[4] Tannus was about 10 years old when his family relocated to Ashqout and there is no information about his early education; the modern historian Kamal Salibi presumes he was homeschooled.
[11] The most important of Tannus's works was Akhbar al-a'yan fi Jabal Lubnan (The History of the Notables in Mount Lebanon), which he completed in 1855.
[13] The first part centered on the natural and political geography of Mount Lebanon and its surroundings and consisted of five chapters: the first chapter defined the boundaries of Mount Lebanon and surveyed its population; the second summarized the histories of the eight principal coastal towns of the Phoenicians, namely Tripoli, Batroun, Byblos, Jounieh, Beirut, Sidon, Tyre and Acre; the third described the mountain's nine main rivers; the fourth detailed the feudal districts of the mountain and the fifth was a table of the population.
[14] The third and longest part of Akhbar al-a'yan dealt with the dynastic and feudal rulers of Mount Lebanon, beginning with the "Mardaite" rulers of the northern parts of the mountain before proceeding in separate chapters, not in chronological order, with the rule of the Buhturids of the Gharb, the Ma'nids of the Chouf, the Assafs of Keserwan, the Sayfas of Akkar, the Shihabs, the Abi'l-Lamas and the Arslans of the Gharb.
[15] Tannus cited as his sources the Maronite historian Ibn al-Qila'i (d. 1516), the Druze historian Ibn Sibat (d. 1520), al-Duwayhi, Haydar al-Shihabi (d. 1821), the biography of Fakhr al-Din II by al-Khalidi al-Safadi (d. 1624), Father Joseph Assemanus (d. 1782), Father Hananiyya al-Munayyir (d. 1820) of Zouk Mosbeh, the Melkite poet Butrus Karami of Homs (d. 1851), and oral and printed histories and court registers of the Shihab, Jumblatt, Khazen, Hubaysh and Talhuq genealogies.
[18] Asad Rustum commented on the Akhbar al-a'yan: "in a way, Shidyak's history is scarcely anything but an account of the Emir [Bashir]'s efforts to rid himself of his rivals".