If you are concerned about the legality of your destination wedding that you had in a foreign country, you can breathe a bit easier. Here is information provided by the U.S. Department of State.
Validity of Marriages Abroad
In general, unless the marriage breaks U.S. state laws, marriages which are legally performed and valid abroad are also legally valid in the United States. Inquiries regarding the validity of a marriage abroad should be directed to the attorney general of the state in the United States where the parties to the marriage live.
Who May Perform Marriages Abroad
American diplomatic and consular officers are not permitted to perform marriages (Title 22, Code of Federal Regulations 52.1). Marriages abroad are almost always performed by local (foreign) civil or religious officials.
As a rule, marriages are not performed on the premises of an American embassy or consulate. The validity of marriages abroad is not dependent upon the presence of an American diplomatic or consular officer but upon adherence to the laws of the country where the marriage is performed. Consular officers may authenticate foreign marriage documents. The fee for authentication of a document is approximately $32.00.
Note: Authentication may not be necessary if the country accepts an Apostille.
Foreign Laws and Procedures
The embassy or tourist information bureau of the country in which the marriage is to be performed is the best source of information about marriage in that country. Some general information on marriage in a limited number of countries can be obtained from Overseas Citizens Services, Room 4811, Department of State, Washington, DC 20520. In addition, American embassies and consulates abroad frequently have information about marriage in the country in which they are located.
Marriages abroad are subject to the residency requirements of the country in which the marriage is to be performed. There is almost always a long waiting period.
Documentation and Authentication
Most countries require that a valid U.S. passport be presented. In addition, birth certificates, divorce decrees, and death certificates are frequently required. Some countries require that the documents presented to the marriage registrar first be authenticated in the United States by a consular official of that country. This process can be time-consuming and expensive.
Persons under the age of 18 must, as a general rule, present a written statement of consent executed by their parents before a notary public. Some countries require the parental consent statement to be authenticated by a consular official of that foreign country in the United States.
Affidavit of Eligibility to Marry
All civil law countries require proof of legal capacity to enter into a marriage contract in the form of certification by competent authority that no impediment exists to the marriage. No such document exists in the United States.
Unless the foreign authorities will allow such a statement to be executed before one of their consular officials in the United States, it will be necessary for the parties to a prospective marriage abroad to execute an affidavit at the American embassy or consulate in the country in which the marriage will occur stating that they are free to marry. This is called an affidavit of eligibility to marry and the fee for the American consular officer's certification of the affidavit is $55.00, subject to change. Some countries also require witnesses who will execute affidavits to the effect that the parties are free to marry.
Many countries, like the United States, require blood tests.
Some countries require that documents presented to the marriage registrar be translated into the native language of that country.
Loss of U.S. Nationality
In some countries, marriage to a national of that country will automatically make the spouse either a citizen of that country or eligible to become naturalized in that country expeditiously. The automatic acquisition of a second nationality will not affect U.S. citizenship. Naturalization in a foreign country on one's own application or the application of a duly authorized agent may cause the loss of American citizenship. Persons planning to apply for a foreign nationality should contact an American embassy or consulate for further information.
Marriage to an Alien
Information on obtaining a visa for a foreign spouse may be obtained from any office of the Bureau of Citizenship and Immigration Services in the Department of Homeland Security, U.S. embassies and consulates abroad, or the Department of State Visa Office, Washington, DC 20520-0113. General information regarding visas may be obtained by calling the Visa Office on 202-663-1225.