European Convention on Nationality

The European Convention on Nationality (E.T.S. No. 166, signed in Strasbourg, 6 November, 1997) is a comprehensive convention dealing with the law of nationality.Common practice among states at the beginning of the 20th century was that a woman was to have the nationality of her husband; thus upon marrying a foreigner she would automatically acquire the nationality of her husband, and lose her own nationality. Even once the nationality of a married woman was made no longer dependent on the nationality of her husband, legal provisions were still retained automatically naturalising married women, and sometimes married men as well. This could lead to a number of problems, including loss of the spouses' original nationality, the spouse losing the right to consular assistance (since consular assistance cannot be provided to nationals under the jurisdiction of a foreign state of which they are also nationals), and becoming subject to military service obligations. For these reasons, the Convention provides that neither marriage nor dissolution of marriage shall automatically affect the nationality of either spouse (article 4d).
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