Background: The risk of stroke after cardiac and carotid surgery is well established. In contrast, stroke risk in association with non-cardiac and non-carotid surgery and its time course are insufficiently known. We investigated the prevalence of recent and planned surgery among patients with stroke and transient ischemic attack (TIA), time dependency of stroke risk, stroke etiology, and interruption of antithrombotic medication in association with surgery. Methods: Data on type and date of surgery and similar interventions within the last year or planned for the next 2 weeks were anonymously collected together with demographic data, vascular risk factors, stroke severity, handicap before stroke and stroke etiology within a state-wide, mandatory, hospital-based acute stroke care quality monitoring project (Rhineland-Palatinate, Germany) for 1 year (2010). Results: Non-carotid and non-cardiothoracic surgery was reported as performed within 1 year before the index event or as planned for the next 2 weeks thereafter in 532 out of 12,120 patients with ischemic stroke/TIA (4.4%). Compared to 91-365 days before stroke/TIA as reference period, risk of cerebral ischemia (per day analysis) was increased for surgery within 61-90 days before ischemia (rate ratio 2.0, 95% CI 1.5-2.8) and continuously increased along shorter intervals between stroke and surgery (31-60 days: rate ratio 3.6, 95% CI 2.9-4.5; 15-30 days: rate ratio 8.2, 95% CI 6.7-10.1; 8-14 days: rate ratio 13.2, 95% CI 10.3-16.8; 4-7 days: rate ratio 16.5, 95% CI 12.2-22.1) peaking at an interval of 1-3 days before ischemia (rate ratio 34.0, 95% CI 26.9-42.8). On the day of surgery, rate ratio was 14.8 (95% CI 7.8-27.9) and for planned surgery it was 2.7 (95% CI 1.8-4.0). Results were similar for first-ever and for recurrent ischemic stroke. Perioperative stroke/TIA was positively associated with atrial fibrillation and cardioembolic stroke etiology, higher mortality, more severe neurological deficits at discharge, and longer hospital stay; and it was inversely associated with microangiopathic etiology and discharge at home. In 34.5% of patients with recent/planned surgery, prior antithrombotic or anticoagulant medication had been interrupted. Conclusions: Recent or planned surgery imposes a considerable short-term stroke risk particularly by cardioembolism with cessation of medication as an important contributor. Stroke after surgery is associated with poor outcome and high mortality. Better strategies to reduce the burden of perioperative stroke are urgently required.