This working paper surveys the business history of the global wind energy turbine industry between the late nineteenth century and the present day. It examines the long-term prominence of firms headquartered in Denmark, the more fluctuating role of US-based firms, and the more recent growth of German, Spanish, Indian and Chinese firms. While natural resource endowment in wind has not been very significant in explaining the country of origin of leading firms, the existence of rural areas not supplied by grid electricity was an important motivation for early movers in both the US and Denmark. Public policy was the problem rather than the opportunity for wind entrepreneurs before 1980, but beginning with feed-in tariffs and other policy measures taken in California, policy mattered a great deal. However, Danish firms, building on inherited technological capabilities and benefitting from a small-scale and decentralized industrial structure, benefitted more from Californian public policies. The more recent growth of German, Spanish and Chinese firms reflected both home country subsidies for wind energy and strong local content policies, whilst successful firms pursued successful strategies to acquire technologies and develop their own capabilities.