Thau too art fallen, Bagdad
So one day may the Crescent from thy Mosque
Be pluck'd by Wisdom, when the enlighten'd arm
Of Europe conquers to redeem the East.
(Robert Southey, Thalaba , V, 72 and 83-85)
Apart from reflecting a dominant facet of the Western literary Orientalism, the above lines, composed in 1801 by the then influential Romantic writer, Robert Southey (1774-1843), appear to be prescient. The consistent US attacks on Muslim countries particularly since 1990s align with the image of "the enlightened West" trying to "redeem the East" by wiping out the "Crescent" and the "Mosque" not only in Baghdad but across the Muslim lands in the Orient.
On studying Literary Orientalism—the corpus of the Western writings on the Muslim lands in the Orient from Medieval to our times—one readily endorses Norman Daniel's following truthful observation:
By misapprehension and misrepresentation an idea of the beliefs and practices of one society can pass into the accepted myth of another society in a form so distorted that its relation to the original facts is barely discernible. Doctrines that are the expressions of the spiritual outlook of any enemy are interpreted ungenerously, and with prejudice, and even facts are modified-and in good faith to suit interpretation. 
Writings representing Literary Orientalism abound in "interpreting ungenerously" all things Islamic, the Prophet Muhammad and the Quran in particular. Islam is misperceived as a Christian heresy, disfigured further by sexual debauchery and violence. The Prophet Muhammad is brazenly portrayed as an impostor. All Islamic articles of faith and practices appear to be shorn of any redeeming feature. In the words of today's leading critic, Matthew Dimmock, Professor of English, University of Sussex, UK, this corpus may be branded as "the history of misrepresentation" or "the misrepresentation of history." 
2. Literature Review
The works listed in “Recommended Reading” give a fair idea of the major writings on Literary Orientalism. Samuel Chew's The Crescent and the Rose (1937) and Norman Daniel's Islam and the West (1962) stand out as the early substantial studies. Since 1980s there have been a spate of critical writings, period-wise which delve into the image of the Orientals/Islam/the East in English literary texts.
Of late, several critical works such as those by Matthew Dimmock, Mythologies of Prophet Muhammad in Early Modern English Culture (2013) and New Turks: Dramatizing Islam and Ottomans in Early Modern England (2005), Frederick Quinn's The Sum of All Heresies: Image of Islam in Western Thought (2007), Sophia Rose Arjana's Muslims in Western Imagination (2015) and Nabil Matar's Turks, Moors and Englishmen in the Age of Discovery (1998) bring out the varied facets of this representation.
3. Research Method
The paper is based on a critical study and close textual analysis of the relevant literary texts of various periods, which portray Islam and Muslims. Reference is made to the origin, and persistence of and modifications in the stereotypes and misperceptions. The discourse is studied in a broader theological, ideological and social-cultural context.
The genesis of Literary Orientalism may be traced back to the violent clashes between Christendom/Europe and Islam and Muslims since the Medieval period in military, religious and political domains. As Islam got entrenched in major areas of Asia and Africa and knocked at the doors of Europe in 8 and 9 centuries, the Church portrayed Muslims as a fierce, irrational heretics, given to violence and lust. The Crusades [1096-1271] aggravated further the divide between Europe and Islam. The Muslim presence in Spain from 711 to 1492 had nonetheless some sobering influence on the Christian-Muslim relations: "As a cultural transplant on the European soil, and a natural bridge between East and West... [Muslim Spain] served as an agent for transmitting basically Eastern ideas." 
The Arabic rhymed verse influenced the love poetry of Guillaume (1071-1127) in the Provencal language. There are unmistakable similarities between the love lyrics of Muslim Spain and the troubadour and trouvere love poetry of Provence, a point strongly endorsed by the Italian writer, Giammaria Barbierie in his Dell' Origine della Poesia Rimita , the Basque author, Estaber Artiqa and the French scholar, Sismondi.  In their love poems both Dante and Chaucer seem indebted to the troubadour poetry, as is evident from Etinenne Sandras's doctoral study.  Chaucer's The Book of Duchess, Franklin's Tale and Troilus and Criseyda are reflective of the same influence.
The twelfth century French oral poetry, Chanson de Geste may be taken as the earliest sample of Literary Orientalism. As to the image of Islam in these heroic Songs, Norman Daniel observes: "The songs relate to actual facts about Islam in the same way as a distorting mirror twists a real object into an unrecognizable travesty."  These Songs represent Islam as a despicable form of paganism and denounce the Islamic practices of the segregation of women, polygamy, divorce, harem and ascribe sexual promiscuity to Muslims. These Songs, in turn, influenced the Middle English Romances, as for example, Beues of Hamtoun and The Sowdone of Babylone which in the words of Dorothee Metlizki, "are essentially the vehicles of fanatical propaganda ... They are primarily concerned with one basic theme: the war of Christianity against Islam."  Another 13th century Romance, Floris and Blancheflue, in the same stereotypical vein, depicts Muslims as irrational pagans and the Prophet Muhammad (peace be upon him) as an impostor. Little wonder then it is to note that William Langland (c. 1330-1386) portrays the Prophet as a Christian heretic in his Piers the Plowman. A note of missionary zeal permeates Chaucer's Man of Law's Tale in which Constance, daughter of the emperor of Rome, converts the Muslim Sultan of Syria. The polemical design of the Tale is heightened by its derisive references to the Quran and the Prophet. A redeeming feature of the Tale, nonetheless, is that it speaks admiringly of a host of Muslim philosophers and scientists. This note features also in the General Prologue, Pardoner's Tale, Book of the Duchess, The Miller's Tale and Astrolabe which recount the Muslim contribution to knowledge. However, John Lydgate's The Fall of Princes (1440) is disfigured by trenchant polemical assaults against the Prophet Muhammad (peace be upon him). In Nicholas Udall's Masque of Turquish Magistrates Muslims are shown committing idolatry!
In the Elizabethan period, Literary Orientalism attained a greater height owing to the political, military and diplomatic encounter between England and the Ottoman Turkey, a superpower of the day. According to Louis Wann, at least 47 plays by major playwrights were staged in Elizabethan period. More significant is their Oriental content and context:
Two-thirds of these Oriental plays were tragedies because the Elizabethans considered the East as the domain of war, conquest, fratricide, lust and treachery. 
How the truth gradually makes it way against falsehood is illustrated by Thomas Browne's Vulgar Errors, which corrects a misconception, originating from the Medieval works on Islam, about Prophet Muhammad's tomb hanging in mid-air, reported by Marlowe in Tambourlaine 2 (1, 1, 137-142), Beaumont in The Scornful Lady, and even at a much later date by Robert Southey in Roderick (XXII-147-150) and Thomas Moore in Lallah Rookh. The Medieval malicious report that the Prophet's body hangs in an iron chest in his mosque in Madina is dismissed by Browne as “evidently false.”  William Dunbar (1456-1513), nonetheless, persists in branding the Prophet as the devil in his Dance of Sevin Deidly Synnis. Sir Walter Raleigh's (1554-1618) The Life and Death of Mahomet teems with calumnies and half-truths. In Marlowe's Tamburlaine Muslim characters appear worshipping the Prophet, betraying as it does Marlowe's ignorance of the Islamic creed of monotheism. Furthermore, the Prophet is linked throughout the play with violence, bloodshed and deceit. In a polemical vein, Muslim characters are shown recanting their Islamic faith on noting the Prophet's imposture. Marlowe holds the unenviable distinction of making a case for the burning of the Quran (Tamburlaine II, 5, i, 172-175). He presses home the Prophet's imposture through Tamburlaine's repeated disavowal and contemptuous rejection of Islam and the Prophet. Shakespeare's plays contain 26 references to Islam and Muslims, though mostly cursory ones. Shakespeare, nonetheless, re-echoes the centuries-old European/Christian misperception about Prophet Muhammad (peace be upon him) as an idol or a false god in Henry IV, Part I (II, iii, 94-95) and King Lear (III, iv, 148). In Romeo and Juliet, he goes a step further in scoffing at him for being a "wretched puling fool/ A whining mammet." The Prophet Muhammad (peace be upon him) is paraded as the object of Muslims' worship in the following Elizabethan plays: Marlowe's Tamburlaine, Fletcher's and Massinger's The King of Malta, Fulke Greville's A Treatise of Monarchy, Robert Greene's Alphonsus, King of Arragon, Robert Daborne's A Christian Turn'd Turk and John Mason's The Turk. So doing these plays replicate the earlier Romances, namely. The Sowdone of Babylon, The Romance of Guy Warwick, Roland and Vernagu, The Taill of Rauf Coilyear, The Siege of Malayne and Sir Ferumbras which show Muslims praying to their god, Prophet Muhammad (peace be upon him). Shakespeare's only direct reference to the Prophet is equally regrettable: in Henry VI, he is presented as an impostor who had trained a dove to eat grain from his ear in order to befool people and to leave the impression of receiving inspiration from the Holy Ghost. Negative images about Islam/Muslims mark the Elizabethan Turk plays, namely Robert Greene's Alphonsus, Robert Daborne's A Christian Turn'd Turk, and Fulke Greville's Mustapha. In his unfinished mock-epic poem, "Metempsychosis or the Progress of the Soul" John Donne (1572-1631) paints a "base, satirical version of the transmission of Prophet Muhammad's light". Likewise, Andrew Marvell (1621-1678) mocks the Prophet Muhammad's "fabrication of divinity" in his “The First Anniversary of the Government (1654)”.
John Dryden's Don Sebastian represents a close thematic affinity with Massinger's Renegado, as he contrasts Christianity with Islam, glaringly in the former's favour. Same holds true for his other play, Almanzor and Almahdie. Alexandar Pope denounce Islamic law and the practice of fratrcide in the Muslim lands in The Dunciad (III, 89-90). In Samuel Butter's Hudibras, Mahomet's kin appear in dark colours (I, 251-252). William Congreve satirizes Islam's "heathenish rules", particularly the prohibition of wine. His other targets of attack are the sensual Muslim Paradise, the supposed Islamic belief about the absence of soul in woman and Prophet Muhammad's for being “a professed opposer of gaiety." (Letter CXI). The Oriental material in Samuel Johnson's corpus is considerable, especially his Oriental Tales which had gained currency in Europe consequent upon the publication and tremendous popularity of the translation of the Arabian Nights. His Irene and Rasselas, having the Oriental setting, though nominal Oriental content, are more concerned about philosophical issues. At least, these do not misrepresent Islam and Muslims. William Cowper (1731-1800) derides Prophet Muhammad (peace be upon him) in his "Love of the World Reproved" (1782) for having forbidden pork.
Oriental Tales published in the wake of the Arabian Nights represent a fascinating facet of Literary Orientalism. Martha P. Conant and Ros Ballaster have categorized these tales as imaginative, moralistic, philosophical and satirical, employing the Oriental "informant voice" "reverse ethnography" and "intellectual engagement" with other cultures. 
Another landmark of pre-Romantic Literary Orientalism is William Beckford's Vathek (1786). Notwithstanding the genuine Oriental setting of and abundant Islamic material in Vathek, its themes are unmistakably Western — the story of Faust lies at its core.
Works of all major Romantic writers stand out for the engagement in varying degrees with the Orient. Coleridge's Lewti and Kubla Khan employ images which bring to mind their possible Oriental sources. Sir Walter Scot's Orientalism as reflected in his Vision of Don Roderick (1811) and The Talisman (1825) resurrects some of the Medieval misconceptions of Islam. As Scott dwells in these works on the Muslim conquest of Spain and Crusades respectively, the polemical note comes to the fore.
Among the Romantics, Robert Southey (1774-1843) has written most about the Orient. His Thalaba the Destroyer, The Curse of Kehama, Roderick, the Last of the Goths, Chronicle of the Cid and his unfinished poem, "Muhammad" are implicated in imperial and missionary ideology. Some allusions to Islam and Muslims feature in Wordsworth's The Prelude, Ecclesiastical Sonnets, particularly Sonnet 34 and "The Armenian Lady's Love." The dream of the Arab in The Prelude (V, 86-102) makes a positive reference to the Arab scholarly tradition and its contribution to the body of knowledge. "The Armenian Lady's Love" nonetheless reiterates the Medieval hostility and revulsion towards Islam. Shelley's Orientalism, as reflected in his Revolt of Islam Queen Mab, Alastor, Hellas and The Assassins, represents the adherence to convention in depicting a negative view of Islam/ the Orient. It is a blatant instance, as in the case of Southey, of the endorsement of the Colonialism and Evangelism of the day. Leigh Hunt's "Mahmoud" and "Cambu Khan" describe with relish the Oriental luxury and gorgeousness. His other poems with distinct Oriental elements are: "Abou Ben Adham," "Jaffar", "The Bitter Gourd", "Abraham and the Fire Worshipper" and "Trumpets of Doolkarnein". Landor's Count Julian centred on the theme of Muslim conquest of Spain, contains several negative observations about Islam and Muslims. Some of Keats' poems testify to his familiarity with the Arabian Nights.
As the British political and military power in the Muslim land was consolidated by early 19th century, the Romantic poetry dealing with the Orient assumed an unmistakable political colour. For a negative perception of the Muslim world, especially its false faith, decayed institutions, despotic political rule and decadent social order, underscored an urgent need for a drastic remedial or reform action on the part of the British, which was deemed as God's will or a moral duty. This intensified support for the civilizing mission and Evangelical work which would ensure reform and enlightenment in the Oriental/Muslim lands. This trend appears at its sharpest in the products of what Marilyn Butler brands as "a school of new powerful politicized poetry."  Some of the works illustrative of this are Southey's long narrative poems, Thalaba, and The Curse of Kehama, Mary Shelley's novel, The Last Man, Shelley's Revolt of Islam, Promethus Unbound and Hellas, Thomas Moore's Lalla Rookh and Byron's “Turkish Tales”, namely “The Giaour,” “The Bride of Abydos,” The Siege of Corinth” and “The Corsair,” and his play Sardanaplus. Most of these works depict revolutions, thoroughly mostly failed ones, aiming at the overthrow of some despotic Oriental ruler. The Evangelical campaign by the Clapham sect urged for Parliament's approval of their conversion mission in India. The Indian society, it argued, reeling under oppressive and cruel Hinduism was “a classical instance of unreformed despotism.”  Eventually the Evangelists won their case in that Parliament amended the East India Act in 1813, permitting proselytisation. Southey and Shelley appear to have joined the call for the civilizing mission or indirectly the imperialism project. Byron's “Turkish Tales”, however, seem to question the validity of the assumptions underlying this project.
To sum up, the distinguishing features of Literary Orientalism in the Romantic period are: a significant advance in both the range and quality of attention to and use of Oriental material; less concern with theological issues in terms of dismissing Islam as a heresy; creative and imaginative articulation of things Oriental and writers appear on firm grounds in engaging with the Oriental world.
Literary Orientalism flourished also in the Victorian period, particularly in the works of Tennyson, Browning and Arnold. A keen interest in the Orient features in such 20 century writers as Yeats, Eliot, Joyce, Kipling, Forster, and Doris Lessing (1919-2013). Constraints of space, however, stop me from delving into the fascinating aspects of the post-Romantic Literary Orientalism.