As soon as the Confederates left Stafford, the Union forces arrived.  They came three different times:

The first Federal Occupation was from April – September 1862 and lasted 5 months

The second Federal Occupation was from November 1862 – June 1863 and lasted 7 months

The third Federal Occupation was only for a month, from May – June 1864.

Thus, Confederates occupied Stafford for 12 months while Union troops were in the county for 13.   At various times during these 25 months there were at least 212,484 Union soldiers and 9,407 Confederates.  Considering that the 1860 census recorded Stafford as having only 8,633 citizens, this was quite an influx during any of these occupations.  Today’s population of Stafford is approximately 138,000, not even close to that of the Union occupation.  The soldiers of both sides changed the landscape of Stafford for decades.  The after-effects of the Civil War were evident until World War II.