What was the relationship between the Slavic and Finno-Ugric tribes? How was their influence on each other expressed?

In those ancient times, the tribes of the Fino-Ugrians lived in the northern lands of Russia (Chud, Merya, all, etc.). At one time, the Finno-Ugrians were annexed to Kievan Rus, paid tribute to it and gave their sons to the army of the prince. Between other regions of the Russian state, the Finno-Ugrians maintained mainly peaceful relations, including trade. There was also a cultural influence on each other. In addition, the northern tribes were actually the last to adopt Christianity during the period of the baptism of Rus.