The complicated relations of the house of Oldenburg in regard to the Danish succes sion, after giving rise to much angry discussion among the princes interested in the ques tion, and the Danish people themselves, led the great powers to enter into a treaty, known as the London treaty of 1852, for settling the question of succession, on the ground that the integrity of the Danish monarchy was intimately connected with the maintenance of the balance of power and the cause of peace in Europe. England, France, Austria, Prussia, Russia, Sweden, and Denmark, were parties to this treaty, in the first article of which it was provided, that on the extinction of the male line of the royal house, prince Christian of Schleswig-Holstein-Sonderburg-Glitcksburg, and his male heirs, to the order of primogeniture, should succeed to all the dominions, then united under the sway of the king of Denmark. The rights of succession, which rested with the Angus tenburg family, were forfeited by a compact with the duke of Augustenburg, entered into for the surrender of his claims, in consideration of a sum of money paid to him by Denmark. The duke's morganatic marriage, and his subsequent rebellion, in 1848, against the Danish king, were the causes which led to the arrangement of this family compact on the existing terms. This treaty, known as the London protocol of May, 1852, was followed in October of the same year by the publication of a supplemtary clause, which stipulated, that on the extinction of the heirs-male of prince Christian of Schleswig Holstein-Sonderburg-Gllicksburg, the II lstein-Gottorp, or imperial Russian line should succeed to the Danish dominions. This article, even more than the original clauses of
the treaty, met with the strongest opposition among the Danes, and after being twice rejected in the Landsthing, the London treaty was only ratified after a new election of members, and on the assurance of the king that in excluding all female cognate lines from the succession, there was no definite intention of advancing the claims of Russia. King Frederick's death, in 1863, brought on the crisis of the much-vexed question of the Danish succession; and although the London treaty was so far followed that prince Christian succeeded as of Denmark, the evils that were anticipated from the meas ure were in 1864 made painfully manifest; for the duke of Augustenburg, notwithstand ing the renunciation by his family of all claims to the succession, appealed to the federal diet for the recognition of his rights on Holstein; and the German powers, glad of a pre text to extend their influence beyond the Eider, occupied the Schleswig-Holsteirr(q.v.)ter ritory, and succeeded, by force of superior numbers, in advancing the boundary of Germany to the borders of Jutland. This led, however, to grave results affecting the whole of Europe. Prussia and Austria took possession of the conquests in their own names. The former power offered the latter pecuniary compensation for, their assistance in the war, while indicating a determination to annex the duchies to its own dominions. Austria refused, and this led to the disastrous battle of Koniggratz. •