Dumbledore's Army (also known as the D.A.) was a secret organization initiated by Harry Potter, Hermione Granger, and Ron Weasley to teach their fellow Hogwarts students proper Defense Against the Dark Arts in 1995. It was founded by Hermione, but taught and led by Harry. This organization was made necessary by the refusal of Dolores Umbridge, the subject's professor during the 1995-1996 school year, to teach anything in her classes other than textbook theory. It was originally founded with twenty-eight members.