Luís Gonzaga Duque Estrada, known as Gonzaga Duque (21 June 1863, Rio de Janeiro - 29 September 1911, Rio de Janeiro) was a Brazilian writer and critic. He was of Swedish descent on his father's side.

After completing his primary education, he enrolled at the prestigious Colégio Abílio [pt], then studied at the Colégio Meneses Vieira. He completed his studies at the Colégio Paixão in Petrópolis. It would appear that he never attended a university.

His best known work, the novel Mocidade Morta (1900, Dead Youth), deals with young artists during the Segundo Reinado [pt], a period from 1840 to 1889, when the Republic of Brazil was established, and their opposition to the prevailing conservativism. The initial reviews were not kind; calling it boring, morbid and full of pseudo-intellectual chatter.^[1] Later, it received some praise for its documentary value.^[2] Recent criticism calls it a significant contribution to understanding the artistic community of late 19th century Brazil and its relationship to the outdated approaches taught at the Imperial Academy of Fine Arts.^[3]

As a critic, he produced the first systematic examination of Brazilian art in his book A Arte Brasileira. This came during a period when the artists there were beginning to make a living entirely from the proceeds of their painting. In 1907, he was a co-founder of the cultural journal, Fon-Fon [pt]. Known to be an unsparing critic in the cause of modernism, his caustic comments about the works of João Zeferino da Costa, who worked in a conservative, classical style, discouraged Da Costa from ever exhibiting again.

A familiar face among Rio's artistic milieu, his portrait was painted by Eliseu Visconti, Belmiro de Almeida, Rodolfo Amoedo and Presciliano Silva [pt], among others. The Brazilian art scholar, Vera Lins, has done a thorough study of his work, which is available online.

• A Arte Brasileira. São Paulo: Mercado de Letras, 1994.
• Mocidade Morta. Rio de Janeiro: Fundação Casa de Rui Barbosa, 1995
• Horto de Mágoas - contos, Vera Lins and Júlio Castañon Guimaraes, Eds. Prefeitura da Cidade do Rio de Janeiro, 1996.
• Impressões de um Amador: textos esparsos de crítica, 1882-1909, Vera Lins and Júlio Castañon Guimaraes, Eds. Belo Horizonte: Editora UFMG, 2001.
• Revoluções brasileiras: resumos históricos. Francisco Foot Hardman and Vera Lins, Eds. Belo Horizonte: Editora UFMG, co-edição Giordano, 1998.

• Guimararães, Júlio Castañon. "Gonzaga Duque: ficção e crítica de artes plásticas". In: Carvalho, José Murilo de, et al. Sobre o pré-modernismo. Rio de Janeiro: Fundação Casa de Rui Barbosa, 1988.
• Lins, Vera. Gonzaga Duque: A Estratégia do Franco-Atirador. Rio de Janeiro: Editora Tempo Brasileiro, 1991. ISBN 978-85-282-0028-7
• Lins, Vera. Gonzaga Duque: crítica e utopia na virada do século. Rio de Janeiro: Fundação Casa de Rui Barbosa, 1996. ISBN 85-7004-182-9
• Vermeersch, Paula. Lista de artigos de Gonzaga Duque na Revista Kosmos. Rotunda. Campinas: Centro de Estudos de Pesquisa das Artes no Brasil (CEPAB), Instituto de Artes, Unicamp, 2003.
• Vermeersch, Paula. Por uma arte brasileira: a pintura acadêmica no final do Segundo Reinado e a crítica de Gonzaga Duque. Rotunda. Campinas: Centro de Estudos de Pesquisa das Artes no Brasil (CEPAB), Instituto de Artes, Unicamp, 2003.

• Casa de Rui Barbosa: Vera Lins: Linhas cruzadas - decifrando o arquivo de Gonzaga Duque, Online.