1. THE CULTIVATION OF SENSIBILITY, EMOTION, PASSION, in opposition to classic rationality [and] common sense . . . .  (The opposition appears clearly in the title of Jane Austen's novel Sense and Sensibility, 1811.)  The Romantics believed that the emotions, spontaneously released, conduce to good conduct.

2. A REVIVED INTEREST IN AND APPRECIATION OF Christianity in general and in particular of CATHOLICISM, now valued for its ritual drama and emotional power.

3. RELISH OF MEDIEVALISM.  The eighteenth century had admired classical Greece and Rome, and used the term "Gothic" in derision.  The Romantics rediscovered the Middle Ages; indeed, they turned it into a rich costume drama which still imposes itself on the historic picture of that time.

4. ACCLAIM OF THE EXCEPTIONAL MAN, THE TRAGIC HERO, the individual genius/rebel who defies society's conventions--the type soon to be known as "Byronic."  The experiences of the exceptional man were bound to be exceptional; hence the Romantic writers favored plots of violent melodrama.

5. TASTE FOR THE MYSTERIOUS, THE FANTASTIC, THE SUPERNATURAL (AND THE NON-EUROPEAN).  The rationalist mood of the early eighteenth century had sought scientific clarity and had [had contempt for] the miraculous, in faith and life.  The Romantics restored the miraculous, perhaps more for its artistic opportunities than out of conviction.  Romanticism gives birth to the "Gothic novel"--for example, Frankenstein.

      6. APPRECIATION OF NATURE, on philosophical as well as aesthetic grounds.  Eighteenth-century literature, even poetry, had been predominantly an urban literature.  The predecessors of the Romantics, the pre-Romantics, opened their eyes to the beauty of wild nature, and described it with loving exactness.  They found a harmony between nature and man; nature is good, and man is good insofar as he cleaves to her. . . .
 
      7.  RESPECT FOR THE SIMPLE, PRIMITIVE MAN, representative of "THE FOLK."  Rejecting the aristocratism of the past, the pre-Romantics and the Romantics found inspiration in the virtues, sufferings, and emotional dramas of the common man, and in those of "the noble savage," uncorrupted by civilization.  A mystical regard for DAS VOLK, especially in Germany, encouraged folkloristic studies, by which the Romantic writers profited.

      8.  CONTEMPT FOR THE BOURGEOIS, THE MIDDLE CLASS man, who is by definition money-grubbing and materialistic, lacking the defiantly unconventional high-mindedness admired by the romantics.
 
Here's another definition of Romanticism (from WebMuseum, Paris: http://www.ibiblio.org/wm/paint/glo/romanticism/); you will see that it stresses the same characteristics already listed.

[Romanticism was an]artistic and intellectual movement that originated in the late 18th century and stressed strong emotion, imagination, freedom from classical correctness in art forms, and rebellion against social conventions.
Romanticism [was an] attitude or intellectual orientation that characterized many works of literature, painting, music, [and] architecture . . . in Western civilization over a period from the late 18th to the mid-19th century. Romanticism can be seen as a rejection of the precepts of order, calm, harmony, balance, idealization, and rationality that typified Classicism in general and late 18th-century Neoclassicism in particular. It was also to some extent a reaction against the Enlightenment and against 18th-century rationalism and physical materialism in general. Romanticism emphasized the individual, the subjective, the irrational, the imaginative, the personal, the spontaneous, the emotional, the visionary, and the transcendental.
Among the characteristic attitudes of Romanticism were the following: a deepened appreciation of the beauties of nature; a general exaltation of emotion over reason and of the senses over intellect; . . . a preoccupation with the genius, the hero, and the exceptional figure in general, and a focus on his passions and inner struggles; a new view of the artist as a supremely individual creator, whose creative spirit is more important than strict adherence to formal rules and traditional procedures; an emphasis upon imagination as a gateway to transcendent experience and spiritual truth; an obsessive interest in folk culture, national and ethnic cultural origins, and the medieval era; and a predilection for the exotic, the remote, the mysterious, the weird, the occult, the monstrous, the diseased, and even the satanic.
 
Of interest is Bertrand Russell's discussion of Romanticism in History of Western Philosophy (London, 1946), p. 703-4.
 
When, in 1815, the political world returned to tranquillity, it was a tranquillity so dead, so rigid, so hostile to all vigorous life, that only terrified conservatives could endure it.  Consequently . . . nineteenth-century revolt . . . took two forms.  On the one hand, there was the revolt of industrialism . . . .  Quite different from this was the romantic revolt, which was in part reactionary, in part revolutionary.  The romantics did not aim at peace and quiet, but at vigorous and passionate individual life.  They had no sympathy with industrialism because it was ugly, because money-grubbing seemed to them unworthy of an immortal soul, and because the growth of modern economic organizations interfered with individual liberty. . . .  The romantic movement is characterized, as a whole, by the substitution of aesthetic for utilitarian standards.  The earth-worm is useful, but not beautiful; the tiger is beautiful, but not useful.  Darwin (who was not a romantic) praised the earth-worm; Blake praised the tiger. But in order to characterize the romantics, it is necessary to take account, not only of the importance of aesthetic motives, but also of the change of taste which made their sense of beauty different from that of their predecessors.  Of this, their preference for Gothic architecture is one of the most obvious examples.  Another is their taste in scenery.  Dr. Johnson preferred Fleet Street to any rural landscape, and maintained that a man who is tired of London must be tired of life.  If anything in the country was admired by Rousseau's predecessors, it was a scene of fertility, with rich pastures and lowing kine.  Rousseau, being Swiss, naturally admired the Alps.  In his disciples' novels and stories, we find wild torrents, fearful precipices, pathless forests, thunder-storms, tempests at sea, and generally what is useless, destructive, and violent.  This change seems to be more or less permanent:  almost everybody, nowadays, prefers Niagara and the Grand Canyon to lush meadows and fields of waving corn.