Son of Duke Alexander of Wuerttemberg and his morganatic wife,
          Countess Claudine Rhedey, from his mother he had inherited a dark
          complexion and good looks. When his cousin became King of Wuerttemberg
          he conferred on Franz the Dukedom of Teck, which was a subordinate
          title of the House of Wuerttemberg.
              Having lost his inheritance through his father's morganatic
          marriage, as an officer in the 7th Imperial Hussars he had been
          virtually living on his military pay and the bounty of the Austrian
          Emperor, with whom he was a favourite.
              The Prince of Wales (Edward VII) met him at Hannover in 1864 and
          invited him to England. It was there that he met Princess Mary of
          Cambridge whom he subsequently married. Their first child, the future
          Queen Mary, was born on the 26th of May 1867 at Kensington Palace.
          Three more children followed.
              On his marriage he had to resign from the Austrian Army and live
          in England on the allowance granted by Parliament to the Princess.
          This dependence and the lack of a career adversely influenced his
          outlook on life and probably aggravated the outbursts of temper to
          which he was prone and which became more frequent as he grew older.
               When Queen Victoria opened the new Law Courts in Fleet Street,
          the Duke of Teck attended the ceremony wearing the full dress uniform
          of a Colonel of the British Army, a rank he had just received for his
          services in the Arabi campaign. The Prince of Wales suddenly assumed,
          in the middle of a conversation, that cold, fixed, wide-eyed stare
          which so unmistakably showed that something was seriously amiss.
          During an embarrassed silence his gaze rested on the Duke of Teck. At
          last he vouchsafed what was displeasing him. "Francis," he said, "has
          got the wrong buttons!"
              Because of Mary Adelaide's extravagance and his vagueness about
          financial matters, they gradually got into debt and had to retire to a
          villa in Florence for a couple of years to try to recoup their
          fortunes. When they returned to England they lived at White Lodge in
          Richmond Park.
              Even before his wife's death, his mind had been failing. He had
          been given to fits of unaccountable laughter, and his conversation
          became incoherent. When he died it was a relief to his family, for his
          mind had gone; also, for two years he had been kept completely
          secluded at White Lodge, surrounded by attendants and not even seeing
          his children.
 

Source: Leo van de Pas