The Kievan-Rus And The Celts Have Currency

Yes, they did.

The Celtic tribes of the Danube valley and surrounding areas - the eastern Celts - issued debased-gold coins in ancient times, imitating the gold staters of Macedonia and the ancient Greek city-states further south. It is surmised that Celtic mercenaries hired by the Greeks brought the coins they were paid with home with them, teaching the Celts the concept of coinage in the process. The further west in Europe you go, the less and less the coins look like their Greek models, until you eventually hit Britain where the coins are extremely abstracted in design. You can see examples of Celtic coinages from various European regions here.

The Kievan Rus and the other northern states were much later coin-issuing entities, well into the mediaeval period. The Zeno.ru coin database has some good examples of coins from these states; see here.