No, you do not need to have any prior military service to be a member of the Indiana Guard Reserve. We provide all the necessary Basic Military Instruction to new recruits without prior military service.
Nonetheless, veterans of any branch of the Uniformed Services, with service verified by DD Form 214 (Certificate of Release or Discharge from Active Duty) or NGB Form 22 (National Guard Report of Separation and Record of Service), are also welcome to join. Accession for prior service veterans is at the last federally recognized rank.