Why By 1848 all but of the nine Italian states were controlled by Austria.?

By 1848, most Italian states were under Austrian control due to a combination of military dominance and political manipulation following the Congress of Vienna in 1815. Austria sought to maintain its influence in Italy to prevent the rise of nationalism and revolutionary movements that could threaten its own stability. Additionally, the lack of unity among the Italian states and their reliance on Austria for protection against external threats contributed to this dominance. The 1848 revolutions across Europe, including in Italy, were attempts to challenge this control, but they were largely unsuccessful in achieving lasting change.