The Slavic peoples are an Indo-European panethnicity living in Central Europe, Eastern Europe, Southeast Europe, North Asia and Central Asia. The term Slavic represents a broad ethno-linguistic group of people, who speak languages belonging to the Slavic language family and share, to varying degrees, certain cultural traits and historical backgrounds. From the early 6th century they spread to inhabit most of Central and Eastern Europe and the Balkans. In addition to their main population centre in Europe, some East Slavs (Russians) also settled later in Siberia and Central Asia. Part of all Slavic ethnicities emigrated to other parts of the world. Over half of Europe's territory is inhabited by Slavic-speaking communities. The worldwide population of people of Slavic descent is close to 400 million for which they rank fourth among panethnicities in the world.

Modern nations and ethnic groups called by the ethnonym Slavs are considerably diverse both in appearance and culturally, and relations between them – even within the individual ethnic groups themselves – are varied, ranging from a sense of connection to feelings of mutual hostility.

The early Slavs were a diverse group of tribal societies in Migration period and early medieval Europe (ca. 5th to 10th centuries) whose tribal organizations indirectly created the foundations for today’s Slavic nations (via the Slavic states of the High Middle Ages).

The first mention of the name Slavs dates to the 6th century, by which time the Slavic tribes inhabited a vast area of central-eastern Europe. Over the following two centuries, the Slavs expanded further, towards the Balkans and the Alps in the south and west, and the Volga in the north and east.

From the 9th century, the Slavs were gradually Christianised, and by the 12th century, they formed the population within a number of medieval Christian states, the East Slavs in the Kievan Rus' and Lithuania, the South Slavs in Bulgaria and Serbia, and the West Slavs in Poland and the Holy Roman Empire (Pomerania, Bohemia).

The question of Slavic origins has generated many theories, none of which have been universally accepted. The competing theories on the origin of Slavs used different types of evidence, had different perspectives upon the issues involved, but also were influenced by political factors. When discussing early "Slavs", one is referring to a diverse set of tribal communities who shared a common language and material culture.