Tuesday, July 2, 2013

New Mapping Technology and the Battle of Gettysburg

About thirty miles from the place where I am typing this, thousands and thousands of people have converged on the town of Gettysburg to commemorate the 150th anniversary of the famous Civil War battle that occurred there from July 1-3, 1863.

Some of you Civil War buffs might be thinking how lucky I am to live so close to this battlefield.  On one level, you are correct.  I usually make between five and ten visits to Gettysburg a year. Sometimes I bring my students, sometimes I bring my family, and sometimes I just walk or drive the ground alone.  Over the years I have even developed some level of comfort in providing a basic tour of the battlefield.

But this week I am staying far away from the site of this important Civil War battle.  I just don't feel like dealing with all the traffic and crowds.  I was in Gettysburg a few weeks ago with my youngest daughter and the place was packed.  I extend my sympathy to friends who actually live in Gettysburg. Janet Vogel, Charles Strauss, and Jill and Sean Titus come immediately to mind.

If you are like me and have decided not to participate in the 150th anniversary festivities you can still get a feel for what happened on July 1-3, 1863 through this very cool interactive map of the decisive moments of the battle.  Here is a brief description:

What more might we learn about this famous battle if we put ourselves in commanders’ shoes, using today’s digital technology to visualize the battlefield and see what they could see? Our team, which includes myself, researcher Dan Miller and cartographer Alex Tait, have done just that. Alex recreated the 1863 terrain based on a superb map of the battlefield from 1874 and present-day digital data. Dan and I captured troop positions from historical maps. Our interactive map shows Union and Confederate troop movements over the course of the battle, July 1 – 3, 1863. Panoramic views from strategic viewpoints show what commanders could – and could not – see at decisive moments, and what Union soldiers faced at the beginning of Pickett’s Charge. You will also find “viewshed” maps created with GIS (Geographic Information Systems). These maps show more fully what was hidden from view at those key moments.

Altogether, our mapping reveals that Lee never had a clear view of enemy forces; the terrain itself hid portions of the Union Army throughout the battle. In addition, Lee did not grasp – or acknowledge – just how advantageous the Union’s position was. In a reversal of the Battle of Fredericksburg, where Lee’s forces held the high ground and won a great victory, Union General George Meade held the high ground at Gettysburg. Lee’s forces were spread over an arc of seven miles, while the Union’s compact position, anchored on several hills, facilitated communication and quick troop deployment. Meade also received much better information, more quickly, from his subordinates. Realizing the limits of what Lee could see makes his decisions appear even bolder, and more likely to fail, than we knew.

I also encourage you to read the special report on the Civil War at Smithsonian.com.