It was at that time that he got close to the Moscow Slavophiles' circle, notably Aleksey Khomyakov and Konstantin Aksakov.

Rybnikov was pronounced "a revolutionary", a fact scathingly commented upon by Alexander Hertzen in Kolokol) and deported to Petrozavodsk.

There he started the extensive study of the Northern Russia's folklore, culture and history.

[1] The Songs Collected by P.N.Rybnikov, published in 4 volumes in 1861—1867 made Rybnikov a well-known author both in Russia and abroad.

He supported the creation of the regional newspaper, Kaliszanin, and was its censor for sixteen years.