Ernest Augustus (German: Ernst August; 20 November 1629 – 23 January 1698), Duke of Brunswick-Lüneburg, was Prince of Calenberg from 1679 until his death, and father of George I of Great Britain.

Therefore, the couple had to live in the Leineschloss at the Hanover court of Ernest Augustus' eldest brother Christian Louis.

Christian Louis died childless in 1665, leaving Lüneburg to the second brother, George William, who had ceded his right to Ernest Augustus, who thus succeeded to that title.

In 1683, against the protestations of his five younger sons, Ernest Augustus instituted primogeniture, so that his territory would not be further subdivided after his death, and also as a pre-condition for obtaining the coveted electorship.

In 1692, he was appointed Prince-elector by the Emperor, thus raising the House of Hanover to electoral dignity, the elevation becoming effective in 1708 when confirmed by the Imperial Diet.