Sardinia professed willingness to accept it, but Austria declined, and on April 23 sent an ultimatum to Victor Emmanuel, demanding unconditional disarmament, which was naturally refused.

On the 29th Austria declared war, and her troops crossed the Ticino--an act which Napoleon had already announced would be considered as tantamount to a declaration of war with France.
With regard to the tone of Mrs.Browning's letters during this period of politics and war, there are a few considerations to be borne in mind.
Her two deepest political convictions were here united in one--her faith in the honesty of Louis Napoleon, and her enthusiasm for Italian freedom and unity.

There were many persons in England, and some in Italy itself, who held the latter of these faiths without the former; but for such she had no tolerance.

Hence not only those who sympathised, as no doubt some Englishmen did sympathise, with Austria, but also those who, while wishing well to Italy, looked with suspicion upon Napoleon's interference, incurred her uncompromising wrath; and not even the conference of Villafranca, not even the demand for Nice and Savoy, could lead her to question Napoleon's sincerity, or to look with patience on the English policy and English public opinion of that day.

The instinct of Italians has been truer.