Which group invaded the Slavic homeland beginning in the ninth century?

The group that invaded the Slavic homeland beginning in the ninth century were the Vikings, specifically the Norsemen from Scandinavia. They traveled along rivers and established trade routes, often engaging in raids and settlements in Slavic territories. This period marked the beginning of significant cultural and political interactions between the Vikings and the Slavic peoples, influencing the development of early medieval states in Eastern Europe.