Talking of his early years Deville wrote, "In 1877 when I was one of those who began to propagate the collectivist and Marxist theory by the newspaper, I scarcely knew the rudiments ... We learned socialism at the same time that we informed our readers, and it is incontestable that we sometimes made mistakes."
Deville's pamphlet Blanqui libre (1878) portrayed Louis Auguste Blanqui, now an old man, as a benign leader who had suffered from oppression.
The pamphlet was vague about Blanqui's revolutionary principles.
In the spring of 1879 Deville tried to give national publicity to the campaign to elect the imprisoned Blanqui as deputy for Bordeaux.
He was the key figure in this Guesdist effort, which was seen as a form of national plebiscite on amnesty for the leaders of the Paris Commune.
In August 1882 Marx visited Paris to visit his two daughters.
Deville, Guesde and Marx's son-in-law Paul Lafargue lunched with him at the home of José Mesa(es) one day, and Marx later told Engels that he was fatigued by their lively talk, filled with "gossip and chatter".
When both Guesde and Deville said they would challenge anyone who called them a coward to a duel, Marx told them the idiocy and immaturity of their comments was offensive.
In 1887 Lafargue's La Socialiste, the organ of the Guesdist movement, was at risk of closing.
Duc-Quercy, Lafarge and Guesde went to Marseille in an attempt to expand circulation.
Deville donated funds from an inheritance, which kept the paper alive until early February 1888, when it ceased publication until September 1890.
In the early 1890s Deville gradually withdrew from formal POF membership, although his work continued to show Guesdist influences.
On July 1, 1893, George Diamandy published the first issue of L'Ère Nouvelle ("The New Era"), a "monthly for scientific socialism".
It viewed itself as both a literary and a sociological review: dedicated to promoting naturalism and historical materialism.
It openly provoking the reading public to explore the work of Émile Zola and attacked "reactionary" critics.
It also proudly called itself "eclectic".
L'Ère Nouvelle hosted articles by Marxist thinkers from the various countries of Europe: primarily Friedrich Engels and Paul Lafargue, but also Georgi Plekhanov, Clara Zetkin, Karl Kautsky, Jean Jaurès, Gabriel Deville and Jules Guesde.
Deville published L'Etat et le Socialisme (1893), Socialisme, révolution, internationalisme (1893) and Principes socialistes (1896).
His Introduction to the abridged Le Capital, de Karl Marx, résumé et accompagné d'un aperçu sur le socialisme scientifique is a masterly summary of Marx's analysis of the process of accumulation.
It was highly effective in making the arguments in Marx's lengthy work accessible to the public.
On 29 April 1907 Deville was appointed Minister Plenipotentiary 2nd class, extraordinary envoy to Ethiopia, but was not installed.
On 16 July 1907 he was appointed delegate of France to the European Commission of the Danube.
On 6 February 1909 he became Deputy Director of Chancery Affairs.
On 5 June 1909 he was appointed Envoy Extraordinary and Minister Plenipotentiary at Athens.
He retired after this.
Gabriel Deville – Assemblée. - Gabriel Deville (in French), Assemblée nationale, retrieved 2017-12-26 http://www2.assemblee-nationale.fr/sycomore/fiche/(num_dept)/2480
Jolly 1960–1977. - Jolly, Jean (1960–1977), "DEVILLE (GABRIEL)", Dictionnaire des parlementaires français de 1889 à 1940, Paris: Presses universitaires de France, ISBN 2-1100-1998-0, retrieved 2017-12-27 http://www2.assemblee-nationale.fr/sycomore/fiche/(num_dept)/2480
Derfler 1991, p. 163. - Derfler, Leslie (1991), Paul Lafargue and the Founding of French Marxism, 1842–1882, Harvard University Press, ISBN 978-0-674-65903-2, retrieved 2017-12-27 https://books.google.com/books?id=L_E_OR6owEEC&pg=PA163
Derfler 1991, p. 166. - Derfler, Leslie (1991), Paul Lafargue and the Founding of French Marxism, 1842–1882, Harvard University Press, ISBN 978-0-674-65903-2, retrieved 2017-12-27 https://books.google.com/books?id=L_E_OR6owEEC&pg=PA163
Hutton 1981, p. 116. - Hutton, Patrick H. (1981), The Cult of the Revolutionary Tradition: The Blanquists in French Politics, 1864–1893, University of California Press, ISBN 978-0-520-04114-1, retrieved 2017-12-27 https://books.google.com/books?id=TqHgvjjKA7kC&pg=PA113
Derfler 1991, p. 166. - Derfler, Leslie (1991), Paul Lafargue and the Founding of French Marxism, 1842–1882, Harvard University Press, ISBN 978-0-674-65903-2, retrieved 2017-12-27 https://books.google.com/books?id=L_E_OR6owEEC&pg=PA163
Hutton 1981, p. 113. - Hutton, Patrick H. (1981), The Cult of the Revolutionary Tradition: The Blanquists in French Politics, 1864–1893, University of California Press, ISBN 978-0-520-04114-1, retrieved 2017-12-27 https://books.google.com/books?id=TqHgvjjKA7kC&pg=PA113
Wright 2017, p. 48. - Wright, Julian (2017), Socialism and the Experience of Time: Idealism and the Present in Modern France, Oxford University Press, ISBN 978-0-19-953358-9, retrieved 2017-12-27 https://books.google.com/books?id=tBonDwAAQBAJ&pg=PA48
Derfler 1991, p. 60. - Derfler, Leslie (1991), Paul Lafargue and the Founding of French Marxism, 1842–1882, Harvard University Press, ISBN 978-0-674-65903-2, retrieved 2017-12-27 https://books.google.com/books?id=L_E_OR6owEEC&pg=PA163
Jolly 1960–1977. - Jolly, Jean (1960–1977), "DEVILLE (GABRIEL)", Dictionnaire des parlementaires français de 1889 à 1940, Paris: Presses universitaires de France, ISBN 2-1100-1998-0, retrieved 2017-12-27 http://www2.assemblee-nationale.fr/sycomore/fiche/(num_dept)/2480
Jolly 1960–1977. - Jolly, Jean (1960–1977), "DEVILLE (GABRIEL)", Dictionnaire des parlementaires français de 1889 à 1940, Paris: Presses universitaires de France, ISBN 2-1100-1998-0, retrieved 2017-12-27 http://www2.assemblee-nationale.fr/sycomore/fiche/(num_dept)/2480
Wright 2017, p. 121. - Wright, Julian (2017), Socialism and the Experience of Time: Idealism and the Present in Modern France, Oxford University Press, ISBN 978-0-19-953358-9, retrieved 2017-12-27 https://books.google.com/books?id=tBonDwAAQBAJ&pg=PA48
Stuart 2002, p. 469. - Stuart, Robert (2002-05-02), Marxism at Work: Ideology, Class and French Socialism During the Third Republic, Cambridge University Press, ISBN 978-0-521-89305-3, retrieved 2017-12-27 https://books.google.com/books?id=mj1CLS5flZEC&pg=PA101
Derfler 1991, p. 206. - Derfler, Leslie (1991), Paul Lafargue and the Founding of French Marxism, 1842–1882, Harvard University Press, ISBN 978-0-674-65903-2, retrieved 2017-12-27 https://books.google.com/books?id=L_E_OR6owEEC&pg=PA163
Derfler 1991, p. 60. - Derfler, Leslie (1991), Paul Lafargue and the Founding of French Marxism, 1842–1882, Harvard University Press, ISBN 978-0-674-65903-2, retrieved 2017-12-27 https://books.google.com/books?id=L_E_OR6owEEC&pg=PA163
Stuart 2002, p. 24. - Stuart, Robert (2002-05-02), Marxism at Work: Ideology, Class and French Socialism During the Third Republic, Cambridge University Press, ISBN 978-0-521-89305-3, retrieved 2017-12-27 https://books.google.com/books?id=mj1CLS5flZEC&pg=PA101
Călinescu 1986, p. 657. - Călinescu, George (1986), Istoria literaturii române de la origini pînă în prezent (in Romanian), Bucharest: Editura Minerva
Voisin 1894, p. 405. - Voisin, André (1894), "Revue des périodiques. L'Ère Nouvelle", Revue Internationale de Sociologie (in French), II – via Gallica http://gallica.bnf.fr/ark:/12148/bpt6k4425844/f415.image
Voisin 1894, p. 405. - Voisin, André (1894), "Revue des périodiques. L'Ère Nouvelle", Revue Internationale de Sociologie (in French), II – via Gallica http://gallica.bnf.fr/ark:/12148/bpt6k4425844/f415.image
Petculescu 1975, p. 36. - Petculescu, Constantin (June 1975), "Lupta revoluționară și democratică a studențimii române. Tineri demni de tinerețea lor", Magazin Istoric (in Romanian)
Jolly 1960–1977. - Jolly, Jean (1960–1977), "DEVILLE (GABRIEL)", Dictionnaire des parlementaires français de 1889 à 1940, Paris: Presses universitaires de France, ISBN 2-1100-1998-0, retrieved 2017-12-27 http://www2.assemblee-nationale.fr/sycomore/fiche/(num_dept)/2480
Stuart 2002, p. 101. - Stuart, Robert (2002-05-02), Marxism at Work: Ideology, Class and French Socialism During the Third Republic, Cambridge University Press, ISBN 978-0-521-89305-3, retrieved 2017-12-27 https://books.google.com/books?id=mj1CLS5flZEC&pg=PA101
Stuart 2002, p. 25. - Stuart, Robert (2002-05-02), Marxism at Work: Ideology, Class and French Socialism During the Third Republic, Cambridge University Press, ISBN 978-0-521-89305-3, retrieved 2017-12-27 https://books.google.com/books?id=mj1CLS5flZEC&pg=PA101
Jolly 1960–1977. - Jolly, Jean (1960–1977), "DEVILLE (GABRIEL)", Dictionnaire des parlementaires français de 1889 à 1940, Paris: Presses universitaires de France, ISBN 2-1100-1998-0, retrieved 2017-12-27 http://www2.assemblee-nationale.fr/sycomore/fiche/(num_dept)/2480
Stuart 2002, p. 272. - Stuart, Robert (2002-05-02), Marxism at Work: Ideology, Class and French Socialism During the Third Republic, Cambridge University Press, ISBN 978-0-521-89305-3, retrieved 2017-12-27 https://books.google.com/books?id=mj1CLS5flZEC&pg=PA101
Jolly 1960–1977. - Jolly, Jean (1960–1977), "DEVILLE (GABRIEL)", Dictionnaire des parlementaires français de 1889 à 1940, Paris: Presses universitaires de France, ISBN 2-1100-1998-0, retrieved 2017-12-27 http://www2.assemblee-nationale.fr/sycomore/fiche/(num_dept)/2480
Gabriel Deville – Assemblée. - Gabriel Deville (in French), Assemblée nationale, retrieved 2017-12-26 http://www2.assemblee-nationale.fr/sycomore/fiche/(num_dept)/2480
Wright 2017, p. 48. - Wright, Julian (2017), Socialism and the Experience of Time: Idealism and the Present in Modern France, Oxford University Press, ISBN 978-0-19-953358-9, retrieved 2017-12-27 https://books.google.com/books?id=tBonDwAAQBAJ&pg=PA48
Wright 2017, p. 49. - Wright, Julian (2017), Socialism and the Experience of Time: Idealism and the Present in Modern France, Oxford University Press, ISBN 978-0-19-953358-9, retrieved 2017-12-27 https://books.google.com/books?id=tBonDwAAQBAJ&pg=PA48
Wright 2017, p. 48. - Wright, Julian (2017), Socialism and the Experience of Time: Idealism and the Present in Modern France, Oxford University Press, ISBN 978-0-19-953358-9, retrieved 2017-12-27 https://books.google.com/books?id=tBonDwAAQBAJ&pg=PA48
Jolly 1960–1977. - Jolly, Jean (1960–1977), "DEVILLE (GABRIEL)", Dictionnaire des parlementaires français de 1889 à 1940, Paris: Presses universitaires de France, ISBN 2-1100-1998-0, retrieved 2017-12-27 http://www2.assemblee-nationale.fr/sycomore/fiche/(num_dept)/2480
Wright 2017, p. 48. - Wright, Julian (2017), Socialism and the Experience of Time: Idealism and the Present in Modern France, Oxford University Press, ISBN 978-0-19-953358-9, retrieved 2017-12-27 https://books.google.com/books?id=tBonDwAAQBAJ&pg=PA48
Jolly 1960–1977. - Jolly, Jean (1960–1977), "DEVILLE (GABRIEL)", Dictionnaire des parlementaires français de 1889 à 1940, Paris: Presses universitaires de France, ISBN 2-1100-1998-0, retrieved 2017-12-27 http://www2.assemblee-nationale.fr/sycomore/fiche/(num_dept)/2480
Jolly 1960–1977. - Jolly, Jean (1960–1977), "DEVILLE (GABRIEL)", Dictionnaire des parlementaires français de 1889 à 1940, Paris: Presses universitaires de France, ISBN 2-1100-1998-0, retrieved 2017-12-27 http://www2.assemblee-nationale.fr/sycomore/fiche/(num_dept)/2480
Gabriel Deville – Assemblée. - Gabriel Deville (in French), Assemblée nationale, retrieved 2017-12-26 http://www2.assemblee-nationale.fr/sycomore/fiche/(num_dept)/2480
Jolly 1960–1977. - Jolly, Jean (1960–1977), "DEVILLE (GABRIEL)", Dictionnaire des parlementaires français de 1889 à 1940, Paris: Presses universitaires de France, ISBN 2-1100-1998-0, retrieved 2017-12-27 http://www2.assemblee-nationale.fr/sycomore/fiche/(num_dept)/2480
Gabriel Deville – Assemblée. - Gabriel Deville (in French), Assemblée nationale, retrieved 2017-12-26 http://www2.assemblee-nationale.fr/sycomore/fiche/(num_dept)/2480
Gabriel Deville (1854–1940) – BnF. - Gabriel Deville (1854–1940) (in French), BnF: Bibliothèque nationale de France, retrieved 2017-12-27 http://data.bnf.fr/12516634/gabriel_deville/