There was really no ancient empire that practiced monotheism. The only two peoples of the western world that practiced it were the Jews and, briefly, the Egyptians. Monotheism in the form of Christianity flourished in the latter part of the Roman Empire, but the empire did not influence Christianity, rather it was the other way around, with Christianity (monotheism) influencing the Roman empire.
Slavic and Greek
Rome influenced Italy.
Byzantine Empire
Iraq
All of the lands which were under the Roman Empire were influenced by the Romans. Countries in the modern nation-state did not exist in antiquity. There were city-states, territories of ethnic groups which were named after the group and kingdoms.
The concept of monotheism was a revolutionary idea that influenced Judaism and Christianity.
It was his mother, St Helena
the introduction of monotheism,and judeo-christian values.
It influenced the culture
India
Many people in the world today worship one god.
Russia
Russia
I think it was when the Romans came through and established the Roman Empire and Christianity and stuff...
Being an island empire.
Slavic and Greek
Rome influenced Italy.