Procol Harum is a British rock band formed in 1967, best known for their iconic hit "A Whiter Shade of Pale", which became a defining song of the Summer of Love. Their music blends rock with classical influences, marked by Gary Brooker’s soulful vocals and Matthew Fisher’s distinctive organ sound. Procol Harum played a key role in the development of progressive rock, and their lyrical themes often leaned toward the poetic and mysterious, thanks to lyricist Keith Reid. Though the lineup changed over the years, the band continued to perform and release music into the 21st century.