Here is some information below please follow link. The reason you are seeing this is because Yelverton Briggs served prior to the Revolutionary War in 1766. Look at the year far left of East Greenwhich, He was probably was already considered a veteran.
Dear Ms. Jones,
Thank you for posting your request on History Hub!
As Mr. Schneider indicated, the record you linked states that he served in 1766. The source is the Rhode Island, Civil and military list, 1647-1800, which is a list of all officers elected by the General Assembly from the organization of the legislative government of the colony to 1800. The National Archives does not have any records concerning service in colonial militias. If any records of the militia have survived, they may be in the custody of the Rhode Island State Archives.
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