In the late 19th century, with the arrival of the first printing press and the founding of the Royal Academy of Belles Letters, Puerto Rican literature began to flourish. The first writers to express their political views in regard to Spanish colonial rule of the island were journalists. After the United States invaded Puerto Rico during the Spanish–American War and the island was ceded to the Americans as a condition of the Treaty of Paris of 1898, writers and poets began to express their opposition to the new colonial rule by writing about patriotic themes.