Power up a recruitment beacon at the Castle and now it will bring in actual Minutemen instead of normal settlers. These new Minutemen can even be moved to other settlements (those already existing will still not be able to be moved)
They are recruited as annoyingly slowly as normal settlers are, so if you’re feeling impatient you could also download one of my mods which directly place either 10 or 20 movable Minutemen into the courtyard of the Castle
