Last week we wrote about how the city of Baltimore was perceived to be unfriendly to the Union. That’s because it was. Lincoln was going to be in a seriously bad place if both Virginia AND Maryland were Confederate. Washington would be done and that would have made it incredibly difficult to manage the Civil War. Hence, the huge Union presence in this city.
There was a large, and historically notable, riot in Baltimore in April 1861. Confederate sympathizers were not okay with the Massachusetts militia passing through their city en route to Washington at the outbreak of the Civil War.
Below is an image depicting the United States flag being raised over the Baltimore customs house on May 1st.
-ad 107-

Source: New York Public Library