In autumn 1612 Floriani settled in Madrid, Spain, where King Philip III commissioned him for a number of projects including to explore the fortifications of Algiers to plan a conquest of the city. In 1617 Floriani was sent to work for the Governor of Milan Pedro Álvarez de Toledo, who had begun an extensive defensive engineering program. Floriani spent about a year in Milan, and although the King of Spain invited him to return to the Algiers project, he declined as he had been commissioned by Archduke Leopold V to fortify the town of Brisach in Hungary. He then took part in strengthening the defences of Pressburg and Vienna. He was present at the Battle of White Mountain in 1620. Within the next couple of years he designed both military and non-military buildings in other cities including Altenburg, until he resigned as a military engineer in 1624.