The technical limitations of surveillance during the American Civil War determined that commanders usually decided where to deploy troops according to what they saw. As we know, Confederate general Robert E. Lee was almost blind in Gettysburg, because his former outstanding cavalry leader, J E B Stewart, did not tell him the position of the Union, and the reconnaissance ability of Confederate scouts was poor. The status of the Confederacy is usually lower than that of the Yankees, which further puts Lee at a disadvantage. Visually, there is a sharp contrast. When federal general Gouvernour K.Warren discovered the allies from the dome and called for reinforcements in time to save the federal defense line,

From this story [×] close to this exclusive clip of 1930.

Confederate veterans went to the microphone and released their version of the terrible slogan video: What is the rebel cry?

Looking at the Battle of Gettysburg through Robert E. Lee's eyes If we put ourselves in the commander's shoes and visualize the battlefield with today's digital technology to see what they can see, what else can we learn from this famous battle? Our team, including myself, researcher dan miller and cartographer Alex Tate, has finished this work. Alex reconstructed the terrain of 1863 according to the battlefield map of 1874 and the current digital data. Dan and I found the location of the army on the historical map. Our interactive map shows the actions of the Union and Confederate forces in the battle from July 65438 to July 3, 65438. From a strategic point of view, the panorama shows what the commander can and can't see at the critical moment, and what the Union soldiers faced when Picot started to attack. You can also find the "Horizon" map created by GIS. These maps show more comprehensively what is hidden in the field of vision at those critical moments.

In short, our map shows that Li never saw the enemy clearly; The terrain itself hides a part of the allied forces in the whole battle. Besides, Lee Myung-bak doesn't understand or admit how advantageous the position of trade unions is. In the Battle of Fort fredericks, Lee Myung-bak's army occupied the commanding heights and won a great victory. In this battle, Union General george meade occupied the commanding heights of Gettysburg. Lee Myung-bak's troops are distributed in a 7-mile arc, and the compact position of the alliance is fixed on several mountains, which is convenient for communication and rapid deployment of troops. Meade also got better information from his subordinates faster. Realizing the limitations that Li can saw made his decision look bolder than we knew, and it was more likely to fail.

Anne Kelly Knowles is a geography professor at Middlebury College. Her historical research works with GIS include EsriPress 2008 and Mastering Iron: The Battle to Modernizing an American Industry, 1800- 1868 (University of Chicago Press, 20 13). 20 12, she won the Smithsonian American History Scholarship for her originality.

Dan miller is a recent graduate of Middlebury College. Dan digitized the position of the troops and conducted historical research to explain the battle. 150 years ago, Dan's ancestors fought in the 82nd Volunteer Infantry Corps in Ohio at Gettysburg, and Dan became fascinated with using GIS technology to investigate.

Alex Tate is the vice president of Ellicot International Map Company. He is engaged in map projects, from civil water battlefields to international border disputes.

Allen Carroll leads a Story Map team in Esri, a leading provider of GIS software and services.

Tim Montenyohl is a three-dimensional artist and animator of international maps.

Judith Nelson is a senior cartographer of international maps.