William Fitz Osbert or William with the long beard (died 1196) was a citizen of London who took up the role of "the advocate of the poor" in a popular uprising in the spring of 1196. Popular revolts by the poor and peasants in England were rare in the 12th century, and quickly and easily suppressed. The fullest known account of the revolt of 1196 comes from the contemporary English historian William of Newburgh in his Historia rerum anglicarum from a chapter entitled "Of a conspiracy made in London by one William, and how he paid the penalty of his audacity".[1]