Political map of Europe & the Mediterranean 4 June 1859 (Battle of Magenta): In April 1859 Sardinia deliberately provoked an Austrian invasion (Second Italian War of Independence), giving the French under Napoleon III (Napoleon III) an excuse to rush to her aid. The French armies used railways to swiftly cross Italy, with the combined Franco-Sardinian forces smashing the Austrians at Magenta (Battle of Magenta) a month later.