The Silesian dialect of the Czech language or the Silesian dialect group contains dialects spoken in areas near the border of the Czech Republic and Poland. Thanks to this geographical position and the mutual contact of the Czech and Polish population in these areas, the Silesian dialect of the Czech language has developed a specific very set of linguistic elements. This thesis deals with the Silesian dialect of the Czech language with an emphasis on its historical and geographical context, as well as its linguistic characteristics. The Silesian dialect is a broad linguistic and geographical term that includes smaller subgroups and types of dialects that form their own separate entities. The main subgroups of this dialect are Silesian-Moravian dialects and Silesian-Polish dialects. These two subgroups also include some even smaller independent linguistic and geographical units. In the case of the Silesian-Moravian dialects, these are the western (Opava) dialectal subgroup, the eastern (Ostrava) dialectal subgroup and the southern (Frenstat) dialectal subgroup. In the case of Silesian-Polish dialects, these are the Karviná dialectal type, the Bohumín dialectal type, the Těšín dialectal type and the Jablunkov dialectal type. This thesis provides a complete linguistic and geographical overview of the Silesian dialect, including all the listed dialectal subgroups and dialectal types.