Why are Whitman's early poems full of romanticism?

Whitman yearned for "freedom" and "democracy" during the French bourgeois revolution since childhood. He hopes that the booming motherland will also become a country full of "freedom" and "democracy". Therefore, his early poems, on the one hand, described the beautiful mountains and rivers of the motherland with bold and colorful brushstrokes and expressed strong patriotic enthusiasm; On the other hand, it also eulogizes the laborers with unrestrained and sincere feelings. During this period, his poems were full of romanticism.