Born in Kronstadt (Transylvania), he studied at the University of Leipzig, after which he went to Amsterdam, where he edited the works of Homer and the Onomasticon of Julius Pollux. Subsequently, in Hamburg, he assisted the major bibliographer Johann Albert Fabricius in the production of his Bibliotheca Graeca and his edition of Sextus Empiricus.
He found a permanent post in Bucharest as secretary to the Prince of Wallachia, Nicholas Mavrocordato, whose work Περὶ τῶν καθηκόντων (De Officiis) he had previously translated for Fritzsch, a Leipzig bookseller, by whom he had been employed as proofreader and literary hack. In Mavrocordatos' library, Bergler discovered the introduction and the first three chapters of Eusebius's Demonstratio Evangelica. In addition to writing numerous articles for the Leipzig Acta Eruditorum, Bergler edited the editio princeps of the Byzantine historiographer Genesius (1733), and the letters of Alciphron (1715), which contained 75 letters published for the first time.
He died in Bucharest, and was buried at his patron's expense. According to another account, Bergler, finding himself without means, left for Istanbul, and died there ca. 1740. He is said to have become a convert to Islam — this report was probably a mistake for the undisputed fact that he embraced Roman Catholicism.