A 1967 rock song, inspired by a famous book, has become an era-defining anthem and is ranked among the best rock songs of all time. The song's origins and inspiration are unclear, with different outlets suggesting different artists and inspirations, including a power female vocalist and a classic novel like "Alice in Wonderland". The song is widely regarded as a timeless classic, with some outlets noting it was written quickly, such as in just an hour, on a broken piano.