Baltasar de Zúñiga y Velasco (1561 – October 1622) was a Spanish diplomat and royal advisor who served as a key minister during the reign of Philip III of Spain. Though not formally titled a ''valido'', he wielded considerable influence over foreign policy and court affairs. Zúñiga also played a decisive role in promoting his nephew, Gaspar de Guzmán, Count-Duke of Olivares, who would become the powerful valido of Philip IV.
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