Czech (/ˈtʃɛk/; čeština Czech pronunciation: [ˈt͡ʃɛʃcɪna]), formerly known as Bohemian (/boʊˈhiːmiən, bə-/; lingua Bohemica in Latin), is a West Slavic language strongly influenced by Latin and German language, spoken by over 10 million people and it is the official language of the Czech Republic. Czech's closest relative is Slovak, with which it is mutually intelligible. It is closely related to other West Slavic languages, such as Silesian and Polish. Although most Czech vocabulary is based on shared roots with Slavic, Romance, and Germanic languages, many loanwords (most associated with high culture) have been adopted in recent years. 

The languages have not undergone the deliberate highlighting of minor linguistic differences in the name of nationalism as has occurred in the Bosnian, Serbian and Croatian standards of Serbo-Croatian. However, most Slavic languages (including Czech) have been distanced in this way from Russian influences because of widespread public resentment against the former Soviet Union (which occupied Czechoslovakia in 1968). Czech and Slovak form a dialect continuum, with great similarity between neighboring Czech and Slovak dialects. (See "Dialects" below.)
Any other languages contribute to it?
It is closely related to other West Slavic languages, such as Silesian and Polish.