After the decline of the Roman Empire in the seventh century, the Arabs had established their domination in Egypt and Persia. Hence the easy accessibility to the Indian commodities like spices, calicoes, silk, and various precious stones that were greatly in demand was affected.
In 1453, Constantinople fell to the Ottoman Turks, which connected the east to west. Hence Merchandise from India went to the European markets through Arab Muslim intermediaries.
The Red Sea trade route was a state monopoly from which Islamic rulers earned tremendous revenues. Also the land routes to India were also controlled by the Arabs.
Fifteenth-century Europe was gripped by the spirit of the Renaissance with its call for exploration.
At the same time, Europe made great advances in the art of ship-building and navigation.
Historians have observed that the idea of finding an ocean route to India had become an obsession for Prince Henry of Portugal, who was nicknamed the ‘Navigator’.
In 1497, under the Treaty of Tordesillas (1494), the rulers of Portugal and Spaindivided the non-Christian world between them by an imaginary line in the Atlantic. Portugal could claim and occupy everything to the east of the line while Spain could claim everything to the west. The situation was thus prepared for the Portuguese incursions into the waters around India.
