Sigma Iota (ΣΙ) was the second Latin American–based Greek lettered inter-collegiate fraternity established in the United States after Psi Alpha Kappa.

These eleven founders were Oscar Emilio Crabb Pacetti, Ernesto "Earnest" Juan Jose Geronimo Ferro, Robusteano Bernardo Ferro, Amito Freire, Francisco Freire, Alberto "Albert" Cecelio Larrieu Torres, John Clement Lombard, Ferdinand Vito Lopez, Edgardo Gregorio Rabel, Emilio Jose Rabel, and Charles Ramond Villa.

[2][3][4][5][6] The rebranded society's first president was Antonio Ramon Güell Gutiérrez from Costa Rica, who would be heavily involved with the growth of the organization on campus in the subsequent years as a fraternity and would become Louisiana State University's first Hispanic professor.

[6][7] La Colonia Hispano-Americano would then change its name to Sociedad Hispano-Americana in December 1904 and LSU would go on to recognize it as a fraternity in the subsequent years according to the Gumbo yearbook.

[11][12] In 1911, the Sociedad Hispano-Americana Medal transformed from a secret society into Sigma Iota, becoming the second known Greek-lettered Latino fraternity after Alpha Zeta.

Meanwhile, Phi Lambda Alpha, a Latino fraternity established in 1919 at the University of California, Berkeley, had plans to expand throughout the United States.