Clay --

I've not read the letter and can't comment on content or tone, but yes, you misunderstood the situation. Most of Maryland and adjacent parts of Virginia were under Federal military control. Legislators, judges and common citizens were arrested and held without charges in military prisons for indefinite terms.

When it comes to American history people (including myself) tend to appreciate basic facts without understanding what they mean. The Civil War ended the voluntary association of states and replaced it with an association based on bayonets. In Southern states, losing the war meant that military governors replaced elected officials, most citizens lost their civil rights and men from outside the region made decisions for them.

That process began in 1861 as parts of Southern states came under Federal control. Occupation didn't end until last Northern troops left in 1876.

Hopefully this provides some background for your October 1863 letter. I'll leave it to others to decide why the writer of the letter thought the situation humorous.