Dear Ms. Rupp,
Thank you for posting you for posting your request on History Hub!
We searched the National Archives Catalog and located Revolutionary War Rolls in the War Department Collection of Revolutionary War Records (Record Group 93) that contains records of various Revolutionary War era units. For more information about these records and other Revolutionary War era records in National Archives custody, please contact the National Archives at Washington, DC - Textual Reference (RDT1) via email at Archives1reference@nara.gov.
Due to the COVID-19 pandemic and pursuant to guidance received from the Office of Management and Budget (OMB), NARA has adjusted its normal operations to balance the need of completing its mission-critical work while also adhering to the recommended social distancing for the safety of NARA staff. As a result of this re-prioritization of activities, you may experience a delay in receiving an initial acknowledgement as well as a substantive response to your reference request from RDT1. We apologize for this inconvenience and appreciate your understanding and patience.
Please contact the Library of Virginia for information regarding Virginia militia. You may also wish to review Research Notes Number 8: Virginia Revolutionary War Records and Virginia Militia in the Revolutionary War : McAllister's Data.
We searched the Research Notes, McAllister’s book, and online and were unable to find any references to a 3rd Regiment of Virginia Militia active during the Revolutionary War. We did locate information about the 3rd Virginia Regiment that indicated it was not a militia unit, but instead was a part of the Virginia Line within the Continental Army. A brief summary of the 3rd Virginia Regiment’s service can be found in The Continental Army by Robert K. Wright, Jr., page 285. There are also multiple published books about the Revolutionary War that provide accounts of the various campaigns in which the 3rd Virginia Regiment participated.
We hope this information is helpful. Best of luck with your research!