Part 1: St. Patrick's Day in 1861 and 1862 Part 2: St. Patrick's Day in 1863 How St. Patrick's Day in the Year 1863 Was Celebrated by The Irish Brigade, A Reminscence by John Ryan America's four-year Civil War often intruded as the Irish under arms geared up to celebrate St. Patrick's Day. Kevin O'Beirne, in Part 3 of 3, looks at the war's late years. (Left: "Corcoran's Irish Legion Drummer, 1…