Alfonso Rodríguez Olmedo was a 17th-century Spanish Jesuit priest who dedicated his life to missionary work among the Guarani people. Born in Zamora in 1599, he entered the novitiate at Villagarcía de Campos before traveling to South America. He distinguished himself by becoming the first missionary to master the local language. In 1626, he joined the Guaycuru missions, eventually traveling to Caaró alongside Roque González. His service ended in 1628 when he was killed by indigenous people in what is now Rio Grande do Sul.