This omnibus brings together some old and some recent works by Jos Gommans on the warhorse and its impact on medieval and early modern state-formation in South Asia. These studies are based on Gommans' observation that Indian empires always had to deal with a highly dynamic inner frontier between semi-arid wilderness and settled agriculture. Such inner frontiers could only be bridged by the ongoing movements of Turkish, Afghan, Rajput and other warbands. Like the most spectacular examples of the Delhi Sultanate and the Mughal Empires, they all based their power on the exploitation of the most lethal weapon of that time: the warhorse. In discussing the breeding and trading of horses and their role in medieval and early modern South Asian warfare, Gommans also makes some thought-provoking comparisons with Europe and the Middle East. Since the Indian frontier is part of the much larger Eurasian Arid Zone that links the Indian subcontinent to West, Central and East Asia, the final essay explores the connected and entangled history of the Turko-Mongolian warband in the Ottoman and Timurid Empires, Russia and China.