Antero Tarquínio de Quental (European Portuguese: [ɐ̃ˈtɛɾu ðɨ kẽˈtal]; old spelling Anthero; 18 April 1842 – 11 September 1891) was a Portuguese poet, philosopher, and writer. Quental is regarded as one of the greatest poets of his generation and is recognized as one of the most influential Portuguese language artists of all time. His name is often mentioned alongside Luís Vaz de Camões, Manuel Maria Barbosa du Bocage, and Fernando Pessoa.
Throughout his life, Quental oscillated between pessimism and depression; afflicted with what might have been bipolar disorder, at the time of his last trip to Lisbon, he was in a state of steady depression, compounded by spinal disease. On September 11 1891, he committed suicide by firing two shots into his mouth while seated on a bench in a garden park in his home town.