Did Lord Castlereagh fulfill his objective in foreign policy?

E. Chamberlain. .
             In 1815 at the Congress of Vienna, Lord Castlereagh represented Britain until he was forced to deal with domestic affairs since he was also leader of the House of Commons. Castlereagh had several main objectives at Vienna. Like Austria, Britain desired a moderate policy towards France. He wanted the establishment of a balance in power in the continent, particularly between French and Russian power. Castlereagh was aiming to minimize the inevitable tensions between the European powers.
             In general terms, Britain had secured the European settlement she wanted. At the end of the Napoleonic wars, "normality" was constituted in Europe for half a century. Castlereagh's next objective was to perpetuate the settlement by initiating a Quadruple Alliance of Britain, Prussia, Russia, and Austria. It aimed at preserving the peace.
             In autumn 1818, the first Congress to meet under the 1815 arrangements assembled at Aix-la-Chapelle. The French government of Louis XVIII was anxious for France to be regarded as a normal monarchical state. A new Quintuple Alliance including France was agreed upon. Castlereagh welcomed this change, as he saw it as sensible diplomacy. .
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             The first ideological threat to Castlereagh's emphasis on equilibrium came from Tsar Alexander I, in the form of the Holy Alliance in 1815. Alexander wanted the powers to sign a strong declaration against all revolutionary movements. After seeing the chaos which had been brought by Napoleon. Alexander claimed Europe was beset with the dangers of Republicanism and Liberalism. Castlereagh did not approve in a religiously led unity, and he distrusted Alexander's motives. He was helped by the fact that Metternich the Austrian Chancellor also declined the offer to join the Holy Alliance. Castlereagh wanted to pre-empt troubles with the Holy Alliance by keeping good relations.
             Although the basic principle of British foreign policy was non-intervention, Castlereagh was in agreement with Metternich on the issue of joint intervention to suppress the Spanish revolution of 1820.