[quote=NarcolepticSailor]The Kingdom of Venice is the area we wish returned which is currently under the control of the Austrian Empire.
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This. ^

The Kingdom of Venice is similar to a state or a province within the Austrian Empire, similar to the Kingdom of Bohemia or the Kingdom of Hungary. It was annexed by Austria after the Napoleonic Wars. Italy would be going to war with us over the status of Venice, not against Venice itself.