Posted by Billy Thomas on March 20, 2005
The phrase does indeed originate in the war between the States. Southern soldiers, mostly country boys, didn't know a lot about the terminology of warfare and therefore "trenches", but they did know about digging ditches, and used the word ditch in place of trench. Under siege at Petersburg Virginia, they vowed to fight the yankees to the "last ditch", refering to the in-depth system of trenches. They dug these "ditches", and were prepared to fight to the last [innermost] one.