This is the 766th most frequent Slovenian word.
slovenskem
"Slovenskem" is the locative or instrumental form of "Slovenia" in Slovenian, meaning "in Slovenia" or "Slovenian" depending on context.
The word 'slovenskem' is used here as an adjective in the locative case (due to the preposition 'na'), describing the noun 'podeželju' (countryside).
Na slovenskem podeželju je zelo mirno.
In the Slovenian countryside, it is very peaceful.
Here, 'slovenskem' describes 'ozemlju' (territory), again showing its adjectival form in the locative case because of the preposition 'na'.
Festival na slovenskem ozemlju je bil veličasten.
The festival on Slovenian territory was magnificent.
The word 'slovenskem' is used here to describe 'jeziku' (language) in the locative case, guided by the preposition 'o' meaning 'about'.