Gregorio de Hinestrosa was born in the Governorate of Chile, part of the Spanish Empire's Viceroyalty of Peru.
Hinestrosa continued this himself and became an officer; he attained the rank of Maestre de Campo, the commander of a colonial militia in Chile.
[1] He went to peninsular Spain to serve in the Franco-Spanish War and distinguished himself in the Siege of Fuenterrabía of 1638 against the French.
Escobar y Osorio rebuked Hinestrosa for construction performed on the home he'd taken for his personal quarters from an army widow.
[3] After Escobar y Osorio's death in 1649, the Paraguayans would elect Hinestrosa's hated rival Bishop Cárdenas as governor.