His Royal Highness Prince Ernst August Christian Georg of Hanover and Cumberland, Prince of Great Britain and Ireland, was born at Penzing near Vienna, the sixth and youngest child of Ernst August of Hanover, 3rd Duke of Cumberland and his wife, the former Princess Thyra of Denmark.1 His father, the exiled Crown Prince of Hanover, succeeded as the Duke of Cumberland in the peerage of Great Britain in 1878. The younger Prince Ernst August became heir apparent to the dukedom of Cumberland upon the deaths of his two elder brothers. He received a commission in a Bavarian cavalry regiment.
In 1884, the reigning Duke of Brunswick-Wolfenbüttel, a distant cousin, died and the Duke of Cumberland claimed to succeed to that territory. However, the Reich chancellor Otto von Bismarck, managed to get the Federal Council (Bundesrat) of the German Empire to exclude him from the succession. Bismarck did this because the duke had never formally renounced his claims to the kingdom of Hanover, which had been annexed to Prussia in 1866. Instead, Prince Albrecht of Prussia became the regent of Brunswick. After Prince Albrecht's death in 1907, the duke was again excluded from the Brunswick succession and the regency continued.
On 24 May 1913, Prince Ernst August of Cumberland married Princess Viktoria Luise of Prussia (13 September 1892-11 December 1980), the only daughter of the German emperor Wilhelm II. The marriage ended the decades-long rift between the House of Hohenzollern and the House of Hanover, that began with the Austro-Prussian War in 1866 (in which Hanover sided with the losing Austria). The wedding of Prince Ernst August and Princess Viktoria Luise was also the last great gathering of European sovereigns (many descended from Queen Victoria and King Christian IX of Denmark) before the outbreak of the First World War. In addition to the German Emperor and Empress and the Duke and Duchess of Cumberland, King George V and Queen Mary of Great Britain, Tsar Nicholas II and Empress Alexandra Feodrovna of Russia attended. Upon the announcement of his betrothal of Princess Viktoria Luise in February 1913, Prince Ernst August took an oath of loyalty to the German emperor and accepted a commission as a cavalry captain and company commander in the Zieten Hussars, a Prussian Army regiment in which his grandfather (George V) and great grandfather (Ernst August I) had been colonels.
On 27 October 1913, the Duke of Cumberland formally renounced his claims to the (former) kingdom of Hanover and the duchy of Brunswick in favor of his surviving son. The following day, the Federal Council voted to allow Prince and Princess Ernst August of Cumberland to become the reigning Duke and Duchess of Brunswick-Lüneburg. The new Duke of Brunswick, who received a promotion to colonel in the Zieten Hussars, formally took possession of his duchy on 1 November. During World War I, he rose to the rank of major-general. On 8 November 1918, he was forced to abdicate his throne along with the other German kings, grand dukes, dukes, and princes. He retired to live on his various estates.
The Duke and Duchess of Brunswick-Lüneburg had five children 2:
Footnotes
1 Under settled practice dating to 1714, as a male-line great grandchild of King George III, Prince Ernst August III of Hanover also held the title of Prince of Great Britain and Ireland with the style of Highness. In the Court Circular printed in the Times (of London) and in the London Gazzette, he was frequently styled Prince Ernest Augustus of Cumberland.
2 By Royal Warrant of 17 June 1914, King George V granted the eldest son and any children thereafter born to Prince Ernst August of Hanover, then reigning Duke of Brunswick-Lüneburg, the title of Prince (or Princess) of Great Britain and Ireland with the style Highness. The provisions of this Royal Warrant ceased with George V's Letters Patent of 30 November 1917, and Hanoverian princes and princesses born after this date were no longer allowed the title Prince of Great Britain and Ireland with the style Highness. However, in 1931, the former Duke of Brunswick-Lüneburg, as head of the House of Hanover and the senior male-line descendant of George III, issued a decree stating that the members of the former Hanoverian royal family would continue to bear the title of Prince (or Princess) of Great Britain and Ireland with the style of Royal Highness. This decree had no legal effect in the United Kingdom, although no British sovereigns since have attempted to stop this practice on the part of the former Hanoverian royal family. The members of the House of Hanover continue to seek the British sovereign's approval when they marry, in accordance with the 1772 Royal Marriage Act.