Boston is a major city in Massachusetts. The city is the home to one of the Espheni towers.
Before the invasion many of the members of the 2nd Mass lived in or around the Boston area, Captain Weaver lived in Allston, a neighborhood of Boston.
For six months, the Massachusetts Militia held Boston, but the city was eventually overrun by Skitters. Following the loss of an important location in the city and the bombing of South Boston in response to heavier resistance, the Militia lost control of the city. In response, Colonel Jim Porter chose to abandon Boston, splitting up his brigade into smaller units and split up to survive.
Eventually an assault was planned on the mothership over the city, the plan was to plant a bomb at each of the legs and detonate them, forcing the mothership to collapse. It was stopped by Airships.
A successful attack was launched however, when an airship entering one of the hangovers was struck by a 2nd Mass Surface to Air Missile, causing the craft to crash inside the Mothership leading to a chain reaction of explosions that caused significant damage and most likely significant loss of life to the aliens.(Eight Hours)
Over 2 years after the invasion Boston was listed as a possible site to attack the Motherships. Boston also currently serves as headquarters for Karen Nadler, commander of the Eastern United States Espheni forces. Tom Mason was brought back to Boston when he was captured by several Skitters and a Mega Mech, after a brief but intense period of interrogation, he managed to escape. After visiting his former home, he made his way back to Charleston, South Carolina.(Strange Brew)
While Colonel Weaver led a diversionary attack on Chicago, Tom led the real attack on the mothership in Boston. Dr. Roger Kadar operated the Volm cannon and fired it, the projectile hit one of the Motherships legs, there was initially little effect. 2 Beamers were sent to attack the cannon, but they were shot down by Ben and Hal. Shortly after the ship collapsed, destroying it. With the destruction the Espheni defense grid collapsed and the Volm troop ship arrived landing over the ruins of the mothership, and the ruins of downtown Boston. The Volm used Boston as their base camp (Brazil) before they mostly abandoned the planet to fight the Espheni elsewhere.