I<span>t was culturally unique from surrounding regions.</span>
The fourth option is the right one. The Swahili city-states grew during the second half of the first millenium thanks to the intense trade activity in the Indian Ocean, <u>India and China had been important trade centers since antiquity and a great trade network had been built over the centuries</u>. Besides the connections between coastal cities of the Indian Ocean, in it's northern part, by the coast of Persia, passed the Silk Road, the trade route that connected Europe to China throughout the Middle Age.
Although it is often claimed that Christians were persecuted for their refusal to worship the emperor, general dislike for Christians likely arose from their refusal to worship the gods or take part in sacrifice, which was expected of those living in the Roman Empire.