The early music revival or the early music movement of Western classical music gained remarkable momentum in the second half of the twentieth century. The field of early music saw much progress not only in academic research, but also in the performance of the music. Through the performances, both live and on records, a wider public became interested in early music and this in turn lit a spark that brought the movement forward. In post-World-War-II United States, Noah Greenberg and the New York Pro Musica was one of the first and most prominent early music ensembles that brought early music closer to public. This thesis closely examines the work of Greenberg and the New York Pro Musica and their contributions to the field of early music performance. With its unusually extensive scope of activities, which ranged from research, education, publication, and recording, to live performance, the New York Pro Musica brought early music to life and established a firm foundation for the field of early music performance in general. An instrumental factor that catalyzed the career of Greenberg and his ensemble was the post-war development of the recording technology and industry. In fact, the New York Pro Musica was initially formed as a recording ensemble and recording continued to serve as a major medium of communication throughout the group's activities, especially under Greenberg. This thesis first examines a wide scope of background conditions that enabled Greenberg and the Pro Musica to succeed as a professional early music ensemble. Then the impact and reception of the group is assessed through an analysis of the published reviews of their recordings. This study offers a deeper understanding of the work and achievement of Noah Greenberg through a thorough observation of his time and situation, and through a focused evaluation of the impact and reception of him and his New York Pro Musica.