Romantic art is not romantic in the contemporary sense. It’s not referring to romantic comedies, or relationships. The meaning has changed since the 19th century. If you describe a person, saying “she is a Romantic” you would be closer the right meaning and usage of the 19th century usage.
The period we call Romanticism covers, generally speaking, from the 1800-1860’s. Its themes were grand! The use of one's imagination and intuition were valued over rational thought. Rational thought brought revolution, war, and destruction. Francisco Goya’s etching is a great example of Romanticism’s reaction to the Age of Enlightenment, and the pining to access something more human than just reason and logic. Many of the early Romantics turned to Nature for inspiration. The scale and the awe of nature became an ideal subject matter to express the inner life, the imagination and what it means to be human — a part of creation rather than separate from it. Our contemporary ideas of connecting Romance to travel, distant lands, awe-inspiring landscapes, can be directly linked back to the art, music and writing of this period.