Goa became the administrative centre of the Portuguese due to its strategic location, military conquest, and economic potential. The Portuguese, led by Afonso de Albuquerque, conquered Goa from the Bijapur Sultanate in 1510. They recognized Goa's immense value as a base for controlling the lucrative spice trade and securing a stronghold in the Indian Ocean against rival powers. Established as the capital of Portuguese India, Goa became the main administrative, commercial, and military center of Portuguese territories in the East. The Portuguese set up a well-defined administrative structure with a viceroy in Goa who governed Portuguese holdings in Asia and beyond, including parts of East Africa and Southeast Asia. The city also served as a religious hub with the establishment of churches and the archbishopric, further consolidating Portuguese influence.
In summary, Goa's rise as the Portuguese administrative center was due to its conquest by the Portuguese military, strategic importance for trade and naval power, and establishment of a formal colonial government headquarters under the viceroy, which controlled multiple Portuguese colonies in Asia.