Maryland soldiers also served in multiple Maryland units, so would be double counted in the aggregate. Dan Toomey is the expert on Marylanders in the Confederate army (author of "The Civil War in Maryland," and "The War came by Train," among other books on Maryland in the Civil War). He has studied both historical and modern rosters of Confederate Maryland units, and adding an estimate of those Maryland soldiers serving in units from other states, comes up with a number between 10,000 and 11,000. This is probably the best estimate.