Romantic Period refers to literary and cultural movements in England, Europe, and America roughly from 1770 to 1860.
Romantic writers (and artists) saw themselves as revolting against the "Age of Reason" (1700-1770) and its values. They celebrated imagination/intuition versus reason/calculation, spontaneity versus control, subjectivity and metaphysical musing versus objective fact, revolutionary energy versus tradition, individualism versus social conformity, democracy versus monarchy, and so on. The movement begins in Germany with the publication of Goethe's Sorrows of Young Werther (about a love-sick, alienated artist type, too sensitive to live, who kills himself; after it was published a number of young men committed suicide in imitation!) and the emergence of various Idealist philosophers (who believed mental processes are the ultimately reality, as opposed to Materialists). The movement then goes to England (Blake, Coleridge, Wordsworth, Shelley, Byron, and Keats), until about 1830 (upon which the Victorian Age begins).
Romanticism does not appear in the U.S. until Irving and Emerson are writing; so, somewhat confusingly, the Romantic Period in the U.S. (1830-1860) overlaps with the period in which U.S. culture may also be said to be "Victorian" (1830-1880). One consequence of the latter: a writer such as Hawthorne is both Romantic and Victorian (he is simultaneously fascinated by and worried about Hester's rebelliousness in The Scarlet Letter). Other works of the period--such as Harriet Beecher Stowe's best-seller Uncle Tom's Cabin--are not "Romantic," but are rather much closer to the realistic fiction of Victorian Britain's George Eliot.
Very generally, we also distinguish "Romantic" from "Classical" values and types of expression, without