A Salafi (Arabic: سلفي‎) is a Muslim who emphasises the Salaf ("predecessors" or "ancestors"), the earliest Muslims, as model examples of Islamic practice. The term has been in use since the Middle Ages but today refers especially to a follower of a modern Sunni Islamic movement known as the Salafiyyah, which is related to or includes Wahhabism, so that the two terms are sometimes erroneously viewed as synonymous. Salafism has become associated with literalist, strict and puritanical approaches to Islamic theology and, in the West, with the Salafi Jihadis who espouse violent jihad against civilians as a legitimate expression of Islam. Academics and historians use the term to denote "a school of thought which surfaced in the second half of the 19th century as a reaction to the spread of European ideas," and "sought to expose the roots of modernity within Muslim civilization."