BACKGROUND AND PURPOSE: Risk of stroke is higher in black Caribbeans in the United Kingdom compared with black Caribbeans in their country of origin. We investigated if these differences were caused by variations in prior-to-stroke risk factors. SUMMARY OF REPORT: Data were collected from the South London Stroke Register (SLSR) and the Barbados Register of Strokes (BROS). Differences in prevalence and management of stroke risk factors were adjusted for age, sex, living conditions prestroke, stroke subtype, and socioeconomic status by multivariable logistic regression. Patients in BROS were on average older (mean difference 4 years) and more likely to have a nonmanual occupation. They were less likely to have a prestroke diagnosis of myocardial infarction (OR, 0.39; 95% CI, 0.19 to 0.77) or diabetes (OR, 0.65; 95% CI, 0.46 to 0.92) and were less likely to report smoking (OR, 0.31; 95% CI, 0.19 to 0.49). They were also more likely to receive appropriate prestroke antihypertensive (OR, 1.88; 95% CI, 1.21 to 2.92) and antidiabetic treatment (OR, 3.33; 95% CI, 1.44 to 7.70) and less likely to receive cholesterol-lowering drugs (OR, 0.19; 95% CI, 0.05 to 0.71). CONCLUSIONS: The higher risk of stroke in black Caribbeans in the United Kingdom might be caused by a higher prevalence of major prior-to-stroke risk factors, differences in treatment patterns for comorbid conditions, and less healthy lifestyle practices compared with indigenous black Caribbean populations.