A lot of people write to me wondering if they should disclose marriages that happened decades ago or the ones that ended in their native countries without the US Government being aware of them. Some people were so upset with their divorces that they destroyed all the files related to the divorce. Others are trying to forget about their past bad marriages. Even others have not told their current spouses or friends that they were married before. The question is if they need not mention this information in their application for naturalization.
The categorical answer is that if you were married and regardless of the outcome (annulment, death, divorce, etc.), the information should be provided to the United States Government, along with all the details asked for in the application. The information is pretty standard and stays in the file that is confidential. The USCIS considers marriages as material information and this is why it insists on having it. Hiding this information is not only a crime (perjury, since you are submitting your application under oath) but enough reason for denial. In fact, not disclosing a marriage may even mean that the USCIS can rescind your green card and initiate deportation proceedings for fraud.