In the late 1850s, he was a Russian diplomatic agent in Bosnia; he published several books about the country and its folklore, thanks to the collaborative efforts of Prokopije Čokorilo.

He died of typhoid while collecting folk songs in Kargopol, in the north of European Russia, and was later reburied in the Novodevichy Cemetery, St. Petersburg.

[1] Hilferding is credited with having coined the term Slovincians (Polish, Słowińcy) to describe the Lutheranized Wends of Hinter Pomerania (also sometimes called Lebakaschuben), but it seems unlikely that he actually did so.

[2] Friederich von Dreger, Prussian Kriegs- und Domänenrat in Pomerania, wrote in 1748: “Most villages [in the region], especially in Hinter Pomerania, remain inhabited by Wends, who also still use the Wendish tongue of the peasants on the other side of the river Stolp [Polish, Słupia River], and church services are held in the same, a language wrongly called Cassubian, because Cassubians, Pomeranias, [and] Poles indeed had one language, but the actual Cassubian lands were where Belgard,.

[4] Florian Ceynowa and Hilferding were not the only ones to study the language and legends of the Kashubians, but they had the greatest influence and prompted others to take up investigations.

Soon after graduating the St. Petersburg University in 1853, he wrote an Essay О сродстве языка славянского с санскритским/O srodstve jazyka slavjanskogo s sanskritskim (On cognition of Slavonic language with Sanskrit).

In this work, he made the first scientific and systematic comparison of the phonetic correspondences between the two languages and provided a list of several hundred cognate words.