Slavs are one of Indoeuropean nations,like Kelts and Germans.They lived in tribes,most of them were horse mans and half nomads,and only "barbarians" who had and used letters.Roman historian described them like very brave warriors half naked. They had smaller and hard horses and short and dark hair and they had no so much pale skin like other Indoeuropens.Every tribe had different god,but they had a main gods to, like Perun,god of thunder,or Svarog,god of Sun.Like Kelts they believed in stars, Moon and Sun,and they had big respect toward nature.Their gods were wooden idols in side of temples.Most of them were war gods like Svantevid(one who see everything),god with four heads,big sword,bow and helmet and other war equipment and they had some types of Druids,they called them Zhrec(hard to translate to English).Today, 40% of soldiers in Foreign legion are Slavs.(sorry for bad English,I am just a Slavic Savage.)
"my kids don't have blue hair or blue eyes,they are real Slavs!"
or,"with their blue hair they look like Shvabo(German),they can't be Slavs.