One of the most important historical periods of Iran in different dimensions is the Safavid period. During this period, Iran's relations with the countries and governments of the time, entered a new phase. One of the most important and stable relations was formed between Iran and India. Meanwhile, the role of the Persian Gulf in the formation and continuation of these relations is very important. Despite the study of various aspects of the role of the Persian Gulf in the relations between Iran and India during the Safavid era, the position of this sea in the evolution of the communication routes of these two countries has not been investigated yet. This research aims to studying the role of the Persian Gulf in the evolution of the communication routes between Iran and India during the Safavid era and its causes. This research has been done with a descriptive-analytical method and a comparative strategy. The data of this research has also been collected in a library manner.
By studying and comparing the collected data, we can conclude that the most important communication route between Iran and India in the first half of the Safavid era was the Kandahar land route. However, in the second half of the Safavid era, this route relatively declined and the sea route of the Persian Gulf became very important. The results of this research also show that the instability of the political situation in Kandahar, the presence of European colonial countries in the Persian Gulf, the change of the Iran-Europe trade route from East-West to North-South and the change of the Safavid capital from Qazvin to Isfahan played an effective role in increasing the role of the Persian Gulf. Although the series of developments in Iran at the end of the Safavid era had caused insecurity in the Persian Gulf, the Kandahar uprising caused the Persian Gulf to continue to be the main way of communication between Iran and India.