when i hear the word Romanticism two things come to mind, the painting of the topless woman in the French revolution painting, and landscape paintings.
the French revolution painting is romantic because it shows everyone fighting and dying as hard as they can for freedom. the picture is enough to stir anyone into a fighting spirit. it is i believe almost a type of early propaganda, it only lacks a catchy phrase. these kinds of paintings and pictures try to put into people an illusion that to fight and die for your nation is a glorious and holy experience. propaganda would evolve into posters but it still looks very similar to the painting i mentioned earlier. during ww2 soviet and nazi propaganda showed similar images of soldiers and citizens fighting, in heroic pose without fear, for their state, not for themselves. a romantic idea, an illusion, and the common belief of many who have not had to go through war.
the landscape is also romantic because it trys to portray an image of perfect nature. i think that this can also be an illusion because landscape never seem to be about deserts or any thing naturally ugly. not to say that a desert is ugly but the artist seem to prefer painting lush forested mountainous landscapes. i also dont recall seeing landscapes of urban areas either. so in a way romantic landscapes are also a bit of an illusion.
so what is Romanticism? i think it is how people show their idea of a perfect world. a world of beauty and innocence. it is a world were ugliness and cowardly feelings dont exist, a world of lies.