Shortly after the end of the Third Crusade, a group of latin hermits were observed living on the slopes of Mount Carmel.
Others, in imitation of the prophet Elijah, led solitary lives on Mount Carmel, especially on that part thereof which overhangs the city of Porphyria, now called Haifa…where in little comb-like cells, those bees of the Lord laid up sweet spiritual honey.
Some time between 1206-14, the papal legate and patriarch of Jerusalem, Albert of Vercelli, wrote a way of life for the hermits. They were to elect their leader (Ch 4), live in separate cells (Ch 6), ponder scripture (Ch 10), pray the Hours (Ch 11), hold possessions in common (Ch 12), gather daily for morning Mass (Ch 14), gather on Sundays for discussions (Ch 15), fast (Ch 16), and work in silence (Ch 20).
Around 1238, the hermits began migrating to the cities of Europe. By 1247, Pope Innocent IV modified their Rule, making them a mendicant order. Since this time, Carmelites have embraced a dual spirituality of contemplative prayer (eremitic/hermit) and active ministry (mendicant/friar).
Over the centuries, many religious and lay groups have become affiliated with the Carmelite Order. Today, the Carmelite family includes friars, contemplative nuns, active sisters, hermits, apostolic institutes, Lay Carmelites, lay missionaries, confraternities, those enroled in the Brown Scapular, those who wear the Brown Scapular, and others.
 Jacques de Vitry. The History of Jerusalem
 From the selected chapters of the Carmelite Rule of St. Albert.