These relationships between "sister nations" occupy a central theme of the magazine during World War I, portrayed as "a suitable moment to create ties between the two states, based on race, traditions and common history, and the notion of Latinity."

[1] Collaborators included: Camilo Pessanha, Delfim Guimarães, Fausto Guedes Teixeira, Afonso Lopes Vieira and Henrique de Vasconcelos also collaborated.

"Atlantida" had as its correspondent director in Paris Graça Aranha, who announced collaborations with Camille Mauclair, Edmond Jaloux, Gaston Riou and François de Miomande.

In the area of plastic arts, Atlantida reprinted in its pages pictures and styles by Alberto de Sousa, Almada Negreiros, António Carneiro, António Soares, Columbano Bordalo Pinheiro, João Vaz, José Malhoa, José Pacheko [pt], Mário Navarro da Costa, Raul Lino, Soares dos Reis and Veloso Salgado.

It is also worth highlighting other contributions by Gabriele d'Annunzio, Guilherme Ferrero and Salomon Reinach.