This article was written to establish the norms in this subject in order to avoid conflicts which may arise in the case of dual nationality.

[22] In 1843, a new constitution was drafted which established that nationality was based upon birth in the territory, or if abroad, to children of Mexican fathers.

[23] The Constitution of 1857 confirmed the provisional conditions with the added requirement those who were naturalized or born abroad had to relinquish their nationality of origin.

[26] This meant that marriages conducted under religious rites without a civil ceremony and registration were invalid, making children born of such unions illegitimate under the law and wives not subject to loss of nationality.

The reverse was also true, in that civil marriage legitimized the children of the union and automatically conferred the nationality of the husband upon the wife.

[28][Notes 1] But, because the Article automatically bestowed nationality unless a foreigner expressly refused it upon purchasing property or having children, Mexican courts were divided on its interpretation.

[28] However, the Mexican Supreme Court in 1881 upheld a decision depriving married sisters Felícitas and Enriqueta Tavares of the right to engage in buying ships for their family business, which was restricted to nationals.

It allowed children born to foreigners within the territory to declare that they claimed Mexican nationality upon reaching their majority and it also accepted naturalization.

[42] Between 1931 and 1934, Chinese expulsion orders, primarily carried out in Sinaloa and Sonora, but also occurring in other states like Baja California and Chiapas, resulted in a large number of families of women who had lost their nationality by virtue of marriage being deported to China.

[48][49][50] In 1933, Manuel J. Sierra, Eduardo Suxrez, and Basilio Vadillo, the Mexican delegates to the Pan-American Union's Montevideo conference, signed the Inter-American Convention on the Nationality of Women, which became effective in 1934, without legal reservations.

[52] Also in 1934 an amendment to the Constitution's Article 30 was drafted which allowed wives who had lost citizenship because of marriage to foreigners to repatriate as naturalized, rather than birthright, Mexicans.

[53] The amendment also allowed Mexican women whether birthright or naturalized to pass on their nationality to their children, but retained the requirement that the father had to be unknown.

[54] In 1937, at the outbreak of the Sino-Japanese War in 1937, President Lázaro Cárdenas allowed 400 women who had lost their nationality by marrying Chinese men to repatriate with their children.

In a 1951 case, the Supreme Court ruled that a Mexican woman had not lost her nationality by marrying a Japanese man.

[53] In 1969, an amendment to Article 30 of the constitution allowed derivative nationality for all children born abroad to a Mexican mother.