fallout

Subdue is a repeatable radiant quest in the Fallout 4 add-on Nuka-World.

Quick walkthrough

Radiant Quest: Subdue 
Speak with Shank during or after Home Sweet Home (followed by Power Play) to select a Commonwealth settlement to turn into a vassal;
choose the option to force them into compliance. 
Choose the gang to assist in taking over the chosen settlement 
Reach the chosen settlement in the Commonwealth and complete the takeover by crippling all settlers and killing all reinforcements. 
Confront the settlement leader to "convince" them to supply the Nuka-World raiders. 
Reward: Variable XP
Chosen settlement becomes a vassal supplying food and improving happiness at nearby outposts 

Detailed walkthrough

During the raider main quest Home Sweet Home, the Sole Survivor will talk with Shank, who instructs them on the finer points of claiming outposts for their raider gangs to begin spreading out into the Commonwealth. After claiming the first outpost and returning, Shank will then request for the Sole Survivor to pick a crop-rich settlement to dominate as a vassal to supply the new outpost. Choosing to pay off the settlers for their crops will trigger the quest Shake Down, while choosing to force the settlers to pay will trigger this quest. Once a choice is made, Shank will offer options for settlements that can be made into vassals, the closer to the outpost the better.

Once a settlement is chosen and a gang selected to provide back up (choosing one will not automatically make them the ones in charge, although not choosing them for it will also negatively affect later quests), Shank says they will assemble close to the target settlement and to meet them there. He will also recommend that the Sole Survivor bring any loose gear to supply the raiders with as they will be carrying standard equipment. As with the previous outpost quest Capture, one can talk to the raider bosses and their lieutenants to get additional tools for accomplishing this task, i.e. fury and/or predator grenades.

Travel to the Commonwealth and reach the map marker where the assembled gang is located. Supply any offered weapons, then give the go-ahead to attack. All named and/or generic settler inhabitants of the settlement will turn hostile, but only their hired gun/Minutemen reinforcements will be non-essential; reducing the HP of the settlers will just result in them being incapacitated. Once the latter are all eliminated, approach the marked settlement leader to complete the takeover of a new vassal, completing the quest. This results in improved happiness at nearby outposts and also fulfills their food requirement.

Quest stages

Quest stages
StageStatusDescriptionLog Entry
20 Meet your Gang outside <Alias=myLocation>My crew is waiting for me near the job location. I guess I shouldn't keep them waiting. Shank also suggested I take along some extra gear to arm up our people.
50 Cripple the Settlers at <Alias=myLocation>Time to put these settlers under the thumb and put any back-up they've got in shallow graves.
55 Kill the Back-Up Defending <Alias=myLocation>
95 Confront the Settlement LeaderThe locals have all been dealt with. Time for me to inform the local leader of our new arrangement.
100Quest finishedQuest completeBingo. A new settlement is now supplying Nuka-World with provisions. Caps and grub all around!
850Quest failedPlayer kicked out of Raiders.

See also