After Bismarck's retirement the emperor attempted to bring about a reconciliation with the duke and the Hanoverians. His attention had been drawn to the bad moral effect of the use to which the Welfen-Fond was applied, and on the duke of Cumberland writing him a letter, in which, while maintaining his claims to the throne of Hanover, he recognized the empire and undertook not to support any enterprise against the empire or Prussia, with the consent of the Prussian parliament the sequestration of his property was removed. The attitude of passive resistance is, however, still maintained, and has affected the position of the duchy of Brunswick.
In 1884 William, duke of Brunswick, died after a reign of fifty-four years. The younger son of the duke who fell at Quatre Bras, he had been called to the throne in 1831 to take the place of his elder brother Charles, who had been deposed. Duke Charles had died at Geneva in 1873, and as both brothers were childless the succession went to the duke of Cumberland as head of the younger branch of the house of Brunswick-Lüneburg. Duke William before his death had arranged that the government should be carried on by a council of regency so long as the heir was prevented from actually assuming the government; at the end of a year a regent was to be chosen from among the non-reigning German princes. He hoped in this way to save his duchy, the last remnant of the dominions of his house, from being annexed by Prussia. As soon as he died the town was occupied by the Prussian troops already stationed therein; the duke of Cumberland published a patent proclaiming his succession; the council of state, however, declared, in agreement with the Bundesrat, that the relations in which he stood to the kingdom of Prussia were inconsistent with the alliances on which the empire was based, and that therefore he could not assume the government. The claim of the duke of Cambridge as the only male heir of full age was referred to the Bundesrat, but the duke refused to bring it before that body, and after a year the Brunswick government elected as regent Prince Albert of Hohenzollern, to hold office so long as the true heir was prevented from entering on his rights. On the death of Prince Albert in September 1906, the Brunswick diet petitioned the Bundesrat to allow the youngest son of the duke of Cumberland to succeed to the duchy on renouncing his personal claims to the crown of Hanover. This was refused, and on the 28th of May 1907 Duke John Albert of Mecklenburg-Schwerin was elected regent by the diet. Under the regency of Prince Albert, Brunswick, which had hitherto steadily opposed all attempts to assimilate and subordinate its institutions to those of Prussia, though it retained formal independence, was brought into very close dependence upon Prussia, as is the case with all the other northern states. In them the armies are incorporated in the Prussian army; the railways are generally merged in the Prussian system; indirect taxation, post office, and nearly the whole of the judicial arrangements are imperial. None, however, has yet imitated the prince of Waldeck, who in 1867, at the wish of his own subjects, transferred the administration of his principality to Prussia. The local estates still meet, and the principality still forms a separate administrative district, but it is managed by a director appointed by Prussia. The chief reason for this act was that the state could not meet the obligations laid upon it under the new system, and the responsibility for any deficit now rests with Prussia.