He was the elder son of Mammadhasan agha Javanshir - heir of Ibrahimkhalil khan of Karabakh - by Khayrunnisa begüm of Ganja.
He cooperated with Russian Empire under the orders of his grandfather during the 1804–1813 Russo-Persian War, routing Kurdish tribesmen of Karadagh.
16 June] 1806 against Iranian army led by his uncle Abu'l-Fath Khan Javanshir and routed them near Zangezur up till Ordubad 4 days later.
[5] Although he failed to achieve this target, to compensate him, Alexander I promoted Jafargulu to colonel rank on suggestion of Gudovich with two medallions - one originally intended for his father and one for his brave in battles against Iranian army on 14 January [O.S.
[1] However, after 4 years, in November 1811 an Iranian courier was apprehended by Russian guards who was bringing a letter to Jafargulu from Abbas Mirza, promising him the title of hakem in return of allegiance to Iran,[1] as well as ordering Jabrayillu clan to obey him.
Although in his later letters to Paulucci he insisted on being set up by Iranian side, his uncle Mehdigulu accused him of treason and blamed losing 60 soldiers on him.
[citation needed] Nevertheless, Iranian army defeated Russian regiments in February 1812, captured 5000-6000 families and installed Jafargulu as khan over them in Karadagh, a bordering region with Karabakh.
Not happy with his situation, he appealed to Nikolay Rtishchev, new viceroy of Caucasus, through his mother to be granted amnesty and return to Karabakh.
Yermolov later arrested Jafargulu and took his 15-year-old son Karim agha as hostage in Tiflis, arguing that he didn't trust him given his previous defection to Iran.
[16] According to Potto, one of the travelers, who saw Jafargulu in 1857, says that he was already a venerable old man, but that even then his handsome, typical face, set off by a full beard, and a colossal figure, bent over years, but saying that there was before a lot of life and strength.
The gravity of his calm movements, his posture and height - everything distinguished him from the crowd of honorary beys, also tall and prominent people, who also did not look like ordinary Azerbaijanis.
A handsome, young, and rich man, he had been very popular in fashionable Petersburg society where he lived a dissipated life.
[19] Jafargulu Agha wrote poems under a pseudonym “Nava” and "Arif" (according to Mir Mohsun Navvab[1]), both in Persian and Azerbaijani languages.
His relative and early friend Gasim bey Zakir was especially critical of him during later life and dedicated a series of poems to him:[20] Rivalry between two poets grew especially worse following Mehdigulu's death in 1845 and Jafargulu's wish to marry his widow Badir Jahan Begüm and cousin Khurshidbanu Natavan to his son Hidayat agha (1821–1888).
Hatred worsened when Zakir's son-in-law Ali bey Fuladov was forced to pay 10-fold of the debt he owed to Jafargulu.