In the early years of his scholarly engagement, Novaković translated into Serbian Leopold von Ranke's monumental work Die Serbische Revolution, as well as its revised and updated edition (1864–1892)[9] as well as the equally famous Histoire de Charles XII by Voltaire (1897) and Joseph Scherr, General History of Literature from German (1872–1874).

He was strongly influenced by internationally renowned professors of Slavic philology and literature, in particular by Pavel Jozef Šafárik, who was living and working in Serbia at the time, and Đura Daničić, the translator of the Bible into the vernacular.

It was at the initiative of Novaković that the Serbian Royal Academy started comprehensive research and collection of various materials available throughout the Serb-inhabited Balkans, which realized the Dictionary of Serbo-Croatian Literary and Vernacular Language.

Although a disciple of Đura Daničić, who was concentrated primarily on linguistic issues, Novaković managed to expand the field of research, establishing a multi-disciplinary approach in treating all the social sciences related to national history, culture and tradition.

Novaković was the Serbian counterpart to the prominent Slavist scholars, philologists such as Czech Dobrovský or Šafárik among Slovaks, Jernej (Bartholomeus) Kopitar and Franz Miklosich among Slovenians, and Vatroslav Jagić among Croats.

His major work on medieval Serbia, the monograph on late Nemanjić period (Serbs and Turks in 14th and 15th centuries), was published in 1893, while his other important works based on unused documents including the studies of pronoia (Pronijari i baštinici) from 1887, village life in the medieval epoch (Selo), a comprehensive social and historical study, from 1891, and The Old Serbian Army (Stara srpska vojska), from 1893, as well as a study on medieval Serbian capitals in Rascia and Kosovo (Nemanjićke prestonice: Ras, Pauni, Nerodimlje), published in 1911, were considered as chapters of the comprehensive, multi-volume monograph The People and the Land in the Old Serbian State (Zemlja i narod u staroj srpskoj državi) which was never fully completed.

In 1907, equally important was the analysis of the struggle between “supreme and central government” in insurgent Serbia: The Constitutional Question and the Law under Karageorge (Ustavno pitanje i zakon Karadjordjeva vremena).

In addition to political works, Novaković published several travelogues, on Constantinople (Pod zidinama Carigrada), Bursa (Brusa) and Turkey-in-Europe (S Morave na Vardar).

He became a professor at the Belgrade's Grandes écoles in 1875, while from 1880 to 1883 he was, for the third time, the minister of education in the Milan Piroćanac conservative Progressive government, when he managed to regulate the status and legal position of both primary and secondary schools.

In order to obtain efficient protection of persecuted Christian Serbs in Ottoman Turkey, Novaković sided with Russia, laying the ground for further political gains in that area.

Appointed anew as Serbian envoy to Constantinople (1897–1900), Novaković organized the first diplomatic action in order to protect Christian Serbs in the vilayet of Kosovo (Old Serbia), that were being persecuted by Muslim Albanian outlaws.

Lacking Russian support, this action, additionally suppressed by Austria-Hungary, did not bring tangible results but raised awareness of both the Serbian and European public of the difficult conditions of the Serbs living under Turkish rule.

More of a cabinet scholar than a political leader, Novaković remained famous for his vast knowledge on various sources, strict methodological approach, dispassionate analysis and patriotic interest in discovering unknown historical data on Serbian history.

Historian Radovan Samardžić called him "a great polyhistor" and noticed Novaković's importance on the development of Serbian historiography and his influence on the work of dr Vladimir Ćorović.