Born in 1774, he was created Duke of Cambridge in 1801. In 1794 he was captured by the French in Flanders but escaped unrecognised. He was highly spoken of as being courageous and amiable, as an 
industrious and efficient soldier. In 1795 he was wounded and called back to England. In 1813 he was sent to Hannover as commander of its army and, when the Congress of Vienna had raised the Electorate to a Kingdom, he was appointed Governor General. As distinct from his brothers, he had neither debts nor mistresses. 

After the death of Princess Charlotte of Wales, his elder brother, the Duke of Clarence, asked him to look around to find a wife for him.Adolphus wrote such glowing reports of Princess Auguste of 
Hessen-Kassel that the Duke of Clarence was greatly amused, saying, "He's in love with her himself. I'll write and tell him to take her, bless him!" And that is what happened: Adolphus, aged forty-four, married the not yet 21-year-old Auguste, on 7 May 1818. In March 1819, a son, George, was born, followed by Auguste in July 1822 and much later, in 1833, another daughter, Mary Adelaide. 
Adolphus, although the most agreeable of George III's sons, was eccentric bordering sometimes on the disturbing, to the point of the Duke of Wellington proclaiming him "as mad as Bedlam". As a young man he read a lot, was interested in science, loved music, and played the violin expertly. 

They spent many years in Hannover. When his son was still young, he caught scarlet fever and the doctors, fearing he might die, sent for the Duke of Cambridge. In his frenzy while attending a dinner, the Duke took a bottle of Steinberger Rhine wine to the boy's bedroom and forced him to drink a glass. The boy improved and for many years Steinberger wine was drunk on young George's birthday. 
In 1837 King William IV died, which separated Great Britain from Hannover. Victoria became Queen of Great Britain and her uncle, Ernest Augustus, King of Hannover, which made the Duke of Cambridge's 
position redundant. Consequently, he and his family returned to England to reside at Cambridge House, Piccadilly. 

To his great disappointment, his son did not marry Queen Victoria but the ineligible Louisa Fairbrother, rumoured to be the mother of two illegitimate children. Louisa was never accepted in the family and 
went through life as Mrs. FitzGeorge. In June 1850, the 76-year-old Duke had a violent stomach attack 
which left him exhausted. From then on he began to decline; so his son, in military service, came back to be with his father. According to his son, he died quite unexpectedly, calmly and quietly. His youngest daughter, Mary, had been with him, but Princess Auguste, Grand Duchess of Mecklenburg-Strelitz, arrived seven hours after he had died. 

Source: Leo van de Pas