Portuguese colonization in the Persian Gulf; Safavid period_* 
At the same time as the major European powers clashed with each other, the Portuguese government, by creating a powerful navy and inventing huge war artillery, attempted to monopolize the maritime trade of the East for its own benefit. The ultimate goal was to eliminate Muslim and European competitors. Portugal first built a strong base in India and then turned its attention to the Persian Gulf, the commercial hub of India. Taking advantage of the negligence of the Safavid kings, who were busy consolidating their newly established government, the Portuguese captured vital bases in the Persian Gulf, including Aden, Muscat, Qalhat, and most importantly, Hormuz (909 AH). Thus, the trade of these regions was in their hands for 117 years until Shah Abbas ordered Imam Qoli Khan to expel them. Imam Qoli Khan first weakened them by transferring trade from Hormuz to the port of Gambrun, and then, upon learning of the British competition and conflict with Portugal, used British force against the Portuguese. By uniting the tribes of Hormuz, the island of Hormuz was finally cleared of the Portuguese presence. In a reckless move (with the support of Shah Abbas and the British ambassador), Imam Qoli Khan completely destroyed the Hormuz trade facilities and then moved the center of trade to the port of Gambrun (which was not an option). The destruction of the Hormuz facilities meant the destruction of seven hundred years of experience in choosing the right place for trade and also monitoring the islands of the Persian Gulf, which resulted in the loss of Iranian dominance over the Persian Gulf and the unbridled presence of England and the Netherlands in the Persian Gulf. 
The more serious consequence was the weakening of Iranian trade from the ground up and for centuries.