The summer of 1863 started off disastrously for the Army of the Potomac in the Eastern Theater. In early May, Confederate General Robert E. Lee's Army of Northern Virginia defeated and humiliated Major General Joseph Hooker's army at the Battle of Chancellorsville. While both armies reorganized in the wake of Chancellorsville's massive losses, Lee then maintained the initiative and launched an invasion of Pennsylvania. Throughout June, Lee's army advanced deeper into Pennsylvania and Northern efforts to stop his progress were ineffective until Major General George Meade replaced Hooker as commander of the Army of the Potomac. On July 1, 1863, Meade and Lee's large armies collided outside of the crossroads town of Gettysburg, Pennsylvania. The stakes were never higher for either army as the newly promoted Meade defended Northern soil, while General Lee risked everything by taking the war into enemy territory. The first day of the Battle of Gettysburg is often overshadowed by fighting on the following days, but July 1 was one of the bloodiest single engagements of the entire Civil War. Many of the decisions leading to and through Gettysburg's first day remain steeped in controversy. Did Meade intend to fight on the Pipe Creek line in Maryland until subordinates such as Major General John Reynolds forced the engagement at Gettysburg? Did the absence of J. E. B. Stuart's cavalry really leave Lee ?blind? to his opponent's movements? Was Lee's desire to avoid a general engagement ignored by his own officers? With neither commanding general on the battlefield for much of the day, crucial decisions remained in the hands of subordinates such as John Buford, John Reynolds, A. P. Hill, Richard Ewell, and Oliver Howard. This Casemate Illustrated volume sets the stage for the Civil War's greatest battle and covers the heroism, decisions, and mistakes made on the first day at Gettysburg. AUTHOR: James Hessler has worked as a licensed battlefield guide at Gettysburg National Military Park since 2003. Jim is the author of Sickles at Gettysburg (2009), and coauthored Pickett's Charge at Gettysburg (2015) and Gettysburg's Peach Orchard (2019). He is one of the few authors to receive the Bachelder Coddington Award multiple times. Jim cohosts the popular Battle of Gettysburg Podcast. His other media appearances include Travel Channel, CSPAN, NPR, and PCNTV. He has contributed articles to Gettysburg Magazine, America's Civil War, and Hallowed Ground Magazine. He was one of the primary content designers for the American Battlefield Trust's mobile Gettysburg application. He is a frequent speaker for Civil War Round Tables and other historical groups nationwide. In addition to Gettysburg, he leads tours of other battlefields and historic sites across the country, and currently sits on the Board of Directors for the Little Bighorn Associates. 120 photographs and illustrations