Final answer:
The Orthodox Church had its greatest missionary success with the Russians, and they continue to play a significant role in shaping Russian history and culture.
Step-by-step explanation:
The Orthodox Church had its greatest missionary success with the Russians. For generations, the Russian Orthodox Church has been the dominant religious denomination in Russia, and they have played a significant role in shaping the country's history and culture. Despite facing challenges from the Soviet era, the Russian Orthodox Church continues to have a strong presence in Russia.