1757 Ferdinand VI Mexico 1/2 Real KM-67 Grades g details. Ferdinand VI, called the Learned (el Prudente) and the Just (el Justo), was King of Spain from 9 July 1746 until his death. He was the third ruler of the Spanish Bourbon dynasty. He was the son of the previous monarch, Philip V, and his first wife Maria Luisa of Savoy.Ferdinand VI's reign proved peaceful, as he avoided involving of Spain in any European conflicts. Moderate changes to Spain were initiated under the king, including reforms of taxation, advance commerce, and the Spanish navy, as well as a ban on freemasonry. However, the last years of Ferdinand's reign were marked by mental instability, much like his direct predecessor Phillip V. Upon his death, Ferdinand was succeeded by his half-brother, Charles III.