Indian music theory has a long, complex, and fascinating history. This presentation will take a broad look at various historical moments which have been pivotal in the evolution of both Hindustani and Carnatic musical practice. Beginning with the Nāṭya-śāstra and the Saṅgīta-ratnākara as foundational texts of a pan-Indic music theory, we will explore not only musical theory per se, but also how musical practice is informed by Indian philosophies of sonic vibration, mathematical precision, aesthetic pleasure, and ultimate salvation. Lastly, we will discuss the rise of new traditions of music theory that arose in the twentieth century as responses to colonialism, modernity, and secularism.