[1] He was a Portuguese-born, Spanish Crown officer, who in 1579 was awarded a large swath of territory in New Spain, known as Nuevo Reino de León.

Carvajal was accused of enslaving large numbers of Indians, a major grievance of the indigenous population fueling the Chichimeca War.

Carvajal was also accused of several other offenses by the Inquisition in Mexico City, but only the charge of concealing that his relatives secretly practiced Judaism was upheld.

[3] In late 1568, Carvajal captured 78 Englishmen marooned on the Tamaulipas coast by John Hawkins, who had lost some of his ships in a fight with the Spanish fleet at Veracruz.

[4][3] In 1572, Viceroy Martín Enríquez de Almanza commissioned Carvajal a captain, sending him to open a road through the mountains between the Pánuco and Mazapil.

This long expedition resulted in the discovery, by Carvajal, of a mountain pass that allowed him to achieve his goal and enabled him to discover the lands that later become Nuevo Reino de León.

He claimed to have punished the natives responsible for the massacre of 400 castaways from three ships wrecked on the coast en route to and from Spain.

[7] In 1578, after obtaining an endorsement from the viceroy and the Audiencia de México for his desire to be granted an important official charge by the king he went to Spain.

[2] Among the privileges granted to Carvajal by the king was that he could recruit, in Spain, up to 100 males, sixty of whom should be married, to be the first colonizers of his Nuevo Reino.

[4] Carvajal was also instructed to civilize, pacify, and Christianize the Indians in his domain, but forbidden to enslave them, an injunction he "never obeyed" in the words of a Mexican essayist.

His original jurisdiction was to comprise a somewhat ill-defined territory, beginning at the port of Tampico, extending along the River Pánuco, and thence turning northward; but it was not to exceed 200 leagues either way.

It would seem to have included Tamaulipas, as well as the states of Nuevo León and Coahuila, and parts of San Luis Potosí, Zacatecas, Durango, Chihuahua and Texas.

[13] As mentioned earlier, the territory granted to Carvajal by Philip II included lands that were contested by other Spaniards living in New Spain.

In late 1588, Carvajal was arrested at Almadén (present day Monclova), which he had allegedly established as a base to carry out slaving raids.

This was based on the accusations that Carvajal's ancestors were New Christians, which contradicted the "Purity of Blood" laws required to obtain permission to settle in the New Spain.