Historians explain the eighteenth-century origin of European colonialism in Asia either with the profile of the merchants or an argument about uneven power. This Element suggests that the environment was an important factor, too. With India (1600-1800) as the primary example, it says that the tropical monsoon climatic condition, extreme seasonality, and low land yield made the land-tax-based empires weak from within. The seaboard supplied a more benign environment. Sometime in the eighteenth century, a transformation began as the seaside traded more, generated complementary services, and encouraged the in-migration of capital and skills to supply these services. The birth of a new state from this base depended, however, on building connections inland, which was still a dangerous and uncertain enterprise. European merchants were an enabling force in doing this. But we cannot understand the process without close attention to geography.