Censuses report over a billion “Hindus” in the world today. But what is “Hinduism”? In answer, many accounts describe the doctrinal evolutions of various quite different currents of thought. To try to reply using material and social evidence is difficult because so many vital primary sources for institutional history remain inaccessible. What were the material foundations of the constellation of religious movements today classed as “Hindu”? How have different forms of religious agency shaped the institutional and religious landscape of a large sweep of Asia? How did such “Hindu” traditions, associated primarily with the ideas and practices of ascetics questing for liberation, become institutionally rooted? And what were the repercussions of the widespread patronage of pious foundations? Three types of sources will be examined: inscriptions, manuscripts, archaeological remains. Inscriptions are crucial because most of our historical knowledge of early South and Southeast Asia is based on epigraphy. We will explore, mine and diffuse these sources with the tools of digital humanities (rich mark-up of proper-names, technical terms, geodata, etc.). In order to contextualise epigraphy, unpublished prescriptive texts and new archaeological data will be adduced. Our goal is to identify and to map regional and interregional patterns of patronage. The actors are varied: “lettrés”, holy men and priestly intermediaries, as well as their patrons, often grandees of the state; but also cenobitic communities with their statutes, their libraries, their educational activities, and their incipient bureaucracy. Through a comparative approach (concentrating on “Hinduism”, but also considering the so-called “heretic” religions Buddhism and Jainism), and in a broad range of regional contexts, we shall attempt to uncover with unprecedented historical depth the complex interplay of religion, state and society in a formative period, the “Śaiva Age”, between the 6th and 13th centuries.