The development of stroke registries has allowed the accumulation of a wealth of data on the descriptive epidemiology of stroke and its evolution in space and in time. For instance, there has been an observed decrease of stroke incidence and mortality in Western Countries during the past 20 years. The use of brain imaging technologies including CT scan and MRI, along with improved cardiac and vascular imaging, has allowed better identification of risk factors for stroke. Hypertension remains the main risk factor for both ischemic and hemorrhagic strokes, and its treatment is effective in reducing first-ever and recurrent stroke incidence. Major medical progress has been achieved in the development of effective medications for hypertension control in the last 2 decades. Despite these advances, we observe large differences in the incidence and mortality rates of stroke throughout the European community. In this review we pose some questions regarding the possible reasons for these differences and we analyze the issue of environmental factors such as meteorological factors and pollution as stroke risk factors.