The Commonwealth: Fallout 4's Boston Wasteland Explained

The Commonwealth is the wasteland around Boston, Massachusetts, and the setting of Fallout 4. Fallout 4's loading screens explain the name: the state was the Commonwealth of Massachusetts before the Great War and has been known only as the Commonwealth since. In 2287 it's a patchwork of settlements, raiders, super mutants and four big factions, with a secret society of scientists hiding underneath it all. (Fallout 4)

Before the bombs#

Pre-war Boston was a high-tech city. Its corporations, labs and military sites show up all over Fallout 4: Mass Fusion's tower downtown, the Commonwealth Institute of Technology across the river in Cambridge, and Fort Strong, an old military base on the harbour. (Fallout 4)

It was also a city under military control. Checkpoints, food riots and soldiers firing on hungry crowds turn up in the terminals and newspaper stories the Sole Survivor finds two centuries later. (Fallout 4)

The Great War in Boston#

Fallout 4's prologue is set in Sanctuary Hills, a suburb north of the city, on the morning of 23 October 2077. News comes in of explosions in New York and Pennsylvania, the sirens start, and the family reaches Vault 111 just as a bomb lands to the southwest. (Fallout 4)

That blast left the Glowing Sea. Fallout 4 calls it the most highly irradiated region in the Commonwealth, and local legend says it was ground zero for the bomb that devastated most of Massachusetts. Downtown Boston, further away, was left battered but largely standing. (Fallout 4)

Two hundred years of rebuilding#

Survivors gathered where they could. The biggest settlement is Diamond City, built inside the walls of Fenway Park, the old baseball stadium, and nicknamed the Great Green Jewel of the Commonwealth. Goodneighbor, a rougher town run by the ghoul mayor John Hancock, takes in the people Diamond City won't. (Fallout 4)

The Commonwealth Minutemen tried to protect them all. Fallout 4's loading screens say they first rose to prominence in 2180, when they defended Diamond City from a horde of super mutants. By 2287 they're down to a handful of survivors led by Preston Garvey. (Fallout 4)

Below everything is the Institute. Its people descend from the scientists and staff of the Commonwealth Institute of Technology who went underground after the war, and they now make synths, artificial people who can pass for human. The Institute also created the Commonwealth's super mutants with its experiments on the Forced Evolutionary Virus. (Fallout 4)

Fear of synths shapes the whole region. Wastelanders suspect their neighbours of being replacements, and even Diamond City's mayor turns out to be a synth. (Fallout 4)

The factions of 2287#

The Sole Survivor wakes in Vault 111 in 2287, 210 years after the war, to find their son Shaun taken. The search drags them into a struggle between four factions:

• The Institute. The hidden scientists below the city, led by a man called Father. (Fallout 4)
• The Brotherhood of Steel. It arrives from the Capital Wasteland aboard the airship Prydwen, under Elder Arthur Maxson, to destroy the Institute and its technology. (Fallout 4)
• The Railroad. A secret network that smuggles synths to freedom. (Fallout 4)
• The Minutemen. The volunteer militia that the Sole Survivor can rebuild into a real force. (Fallout 4)

Which of them comes out on top depends on the player, and the games haven't confirmed a canon ending. (Fallout 4)

Where it was first mentioned#

The Commonwealth was set up years before Fallout 4. In Fallout 3, a man called Dr. Zimmer comes to Rivet City from the Commonwealth to hunt a runaway android, and the Lone Wanderer can learn that the escaped machine is hiding in plain sight. (Fallout 3)

The Commonwealth in the TV series#

The show hasn't visited Boston, but it matters to the plot. In the first episode, the Brotherhood's Elder Cleric Quintus says the mission to catch a runaway Enclave scientist comes from the highest clerics in the Commonwealth. The Commonwealth chapter, in other words, now gives the orders. (Fallout, "The End")

Season 2 shows why. A Brotherhood paladin, Xander Harkness, tells Maximus they're in serious trouble back home, and that without the cold fusion relic they risk losing the Commonwealth, and civilisation with it. The show hasn't said what the threat is. (Fallout, "The Profligate")

For the full story of the game, see Fallout 4's story explained.