In 1819 he made one speech in parliament in which his declared his
belief that Roman Catholic Emancipation was impossible, unless there
could be a proper security for the Protestant religion, which he
doubted.

In the year 1823, on the appointment of Mr. Canning to be Secretary for
Foreign Affairs, Duke of Wellington was named as the Plenipotentiary of
the King of Great Britain at the Congress of Verona. It was supposed
that the subject matter of the discussions of the sovereigns at that
congress would be the relations of Russia and Turkey. On the Duke's
arrival at Paris, however, he found that Spain would form the main
subject. He wrote back for fresh instructions, and Mr. Canning's answer
distinctly stated that should France attempt to interfere in Spain
either by force or by menace, he was to instruct the Duke "frankly and
peremptorily to declare, that to any such interference, come what may,
his majesty will not be a party."

The words "frankly and peremptorily" could not have been better chosen,
or more agreeable to the character of the Duke. He stuck simply and
stedfastly to his text throughout the negotiations, and when at last, in
consequence of the state of affairs in Spain, the three great powers
agreed to withdraw their ministers from Madrid, the Duke told them he
should not withdraw ours but leave him there in the hope of allaying the
irritation which the measures of the others were calculated to produce.

The Duke returned to Parts in December, and found the French not
indisposed to some arrangement. When it subsequently became necessary to
send a special communication to the Spanish government, a mark of
respect was paid by Mr. Canning to the Duke of Wellington, more