Giovanni de Galliano Pieroni

Giovanni de Galliano Pieroni (1586–1654) was a military engineer specialized in erecting fortifications, architect, mathematician and astronomer who gained particular fame in his day as also as author of horoscopes.

During that time he befriended Galileo, who served then the Tuscan Grand Duke, Cosimo II di Medici.

[2] Since 1639, he documented the state of fortifications in Croatia and along the Military Frontier on behest of the Hofkriegsrat, the Imperial war council.

[3] After the end of the Thirty Years' War, Pieroni was in charge of the repair and expansion of Prague's fortifications under the city commanders Innocentio Conti and Jan van der Croon.

[4] Van der Croon and Pieroni also took responsibility for constructing the defensive walls of Náchod castle for its owner Ottavio Piccolomini.

View of Ljubljana , drawn by Giovanni Pieroni. Pieroni travelled around the Habsburg monarchy as a military engineer, and left a series of drawing and sketches of Central European towns and fortresses.