Names of eras, or movements, are generally given after the time period wanes. Scholars look closely at a time period and notice general trends in thought. The specific years of certain genres can be debated, and not all authors who write at a certain time reflect all of these themes. The Romantic era is used to describe not only literature but also common ideas in music and art. Some scholars say this period went from 1800 to 1850. The eNotes study guide suggests even more specific dates, from 1789 to 1832. Other people suggest a more broad definition of the Romantic era as the late 18th century through the 19th century. The Romantic era describes the common ideas of writers (and other artists and thinkers) after the Enlightenment.

Romantic literature is not the same as romance literature. The term "Romantic" does not refer to love and marriage. Instead, it refers to common themes like imagination, truth, nature, beauty, individualism, and the supernatural, as well as other ideas. These themes are found in poetry, novels, and other writings from the Romantic period. Some famous English Romantic poets include John Keats, William Wordsworth, and Samuel Taylor Coleridge. One of Keats's most famous poems, "Ode on a Grecian Urn," has a famous line reflecting a couple of Romantic themes:

Beauty is truth, truth beauty,—that is all

Ye know on earth, and all ye need to know. (lines 49–50)

I wandered lonely as a cloud That floats on high o'er vales and hills, When all at once I saw a crowd, A host, of golden daffodils; Beside the lake, beneath the trees, Fluttering and dancing in the breeze. (lines 1–6)

The Romantics felt that the experience of intense emotion was of far greater value and merit than the exercise of logic.  To them, the ability to feel intense emotion is something that we are all born with, and so they felt that it was somehow fundamental to our humanity.  We must learn logic, unlike emotion, and so it seemed of lesser value to them. 

For the Romantics, experiencing nature, especially the sublime in nature -- the great beauty and tranquility of a sunset, the overpowering hopefulness associated with sunrise, the awesome terror created by a powerful thunderstorm -- would help to restore human beings to a more fundamental state.  This often had to do with nature's ability to inspire intense emotion with us; they felt that experiencing and appreciating nature was morally improving.

The Romantics very much respected the idea of the artistic genius, someone who seemed to be inherently able to tap into supreme creativity and expression via art -- whether it be poetry or painting or something else. 

In general, some major principles or themes of Romanticism were:

• The importance of emotion.  Romantics believed that people should heed their emotions rather than trying to be logical and rational.
• Nature.  They felt that nature was important and that people ould learn from it.  They felt that people should try to "connect" with nature.
• Pantheism.  This is related to the last point.  The idea of many gods representing, for example, aspects of nature would appeal to romantics.
• Dreams and visions.  This is related to the first point.  They thought these had deep meaning and claimed (Coleridge and "Kubla Khan" for example) at times to get their poems in dreams

There are others, but these are the ones that are most important.