Guillaume Raynal attacked slavery in the 1780 edition of his history of European colonization. He also predicted a general slave revolt in the colonies, saying that there were signs of "the impending storm". One such sign was the action of the French revolutionary government to grant citizenship to wealthy free people of color in May 1791. Since white planters refused to comply with this decision, within two months isolated fighting broke out between the former slaves and the whites. This added to the tense climate between slaves and "grands blancs".