This detachment was formed in 2002 with a meeting of local Marines at Georges Cafe in Brockton Massachusetts. The group decided on the name, Metro South Marine Corps League Detachment 1115. In 2004 the United States was involved in two major conflicts in Iraq and Afghanistan. In 2004 Massachusetts lost Marine 1st Lt.Brian McPhillips of Pembroke Massachusetts to action in Iraq. This loss had a huge impact on the community and many in the Detachment felt changing the name of the Detachment would be an great way to honor 1st Lt. Brian McPhillips.
In 2014, The Metro South Detachment 1115 reformed and rewrote the charter to rename the Detachment after 1st Lt Brian McPhillips. The new official name of the Detachment is now 1st Lt. Brian McPhillips Metro south Detachment 1115.