Provided herein are non-naturally occurring, broadly reactive, pan-epitopic antigens derived from H3 influenza virus that are immunogenic and are capable of eliciting a broadly reactive immune response, such as a broadly reactive neutralizing antibody response, against H3 virus following introduction into a subject. Also provided are non-naturally, broadly reactive occurring immunogens, vaccines, virus-like particles (VLPs) and compositions comprising the immunogens and vaccines. Methods of generating an immune response in a subject by administering the immunogens, vaccines, VLPs, or compositions thereof are provided. In particular, the immunogens comprise the hemagglutinin (HA) protein of H3 influenza virus strains.