In which country are shia imams particularly important and influential?

in any shia country

Twelver shia Muslims live in many countries. Iran is the main Shia county and the leader of Shia Islam in world. Twelver Shia Islam constitute the majority of the population in Iran (90%), Azerbaijan (75%), Bahrain (70%), Lebanon (65% of Muslims) and Iraq (65%), Yemen (45%). Other countries with a significant proportion of Shia are Syria (15%), Kuwait (35%), Pakistan (20%), India (23% of Muslims), Afghanistan (15%), Saudi Arabia (18%), Turkey (20%), United Arab Emirates (16%), Qatar (15%), Albania(25%).

other Muslim countries are mainly sunni with minor shia population. Qum in Iran and Najaf in iraq are two main city of Shia Islam.