Do you mean to say South African?
Please contact a lawyer and do not make legal decision based on the legal advice provided. Criminal cases are complex and factually very sensitive.
The answer will be found in the law of "SA," wherever that is.
This answer is offered as a public service for general information only and may not be relied upon as legal advice.
The answer is whatever jurisdictiion SA has will control.
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In general terms, any country that would allow a citizen to hold dual US citizenship would recognize a divorce legally obtained in the US. However, as my colleagues have answered, to be absolutely certain you would need to confer with an attorney in South Africa, as well as to determine what steps, if any, are necessary for recognition to occur (some countries have very specific processes and requirements).
Responses are for general information purposes only, and are based on the extremely limited facts given. A consultation with an attorney experienced in the area of law(s) indicated in the question is highly recommended. Information and advice given here should not be relied upon for any final action or decision, as the information is limited by its nature to the question asked and the fact(s) presented in that question. THIS RESPONSE DOES NOT CREATE AN ATTORNEY/CLIENT RELATIONSHIP, particularly considering that the names of the parties are unknown.
Most jurisdictions around the world recognize divorces that observe the same vague formalities as in that jurisdiction. The US recognizes marriages as long as similar vows were made to that of a US marriage. You would need to look at the law of South Africa. My guess is that they will recognize a US marriage, but I don't know for sure.