diff --git a/CHANGELOG.md b/CHANGELOG.md
index 7a7ab5d3ff..ae31e39e12 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -9,6 +9,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 * The `User-Agent` header set in the linkcheck HTTP(S) requests can now be customized with the `linkcheck_useragent` option to `makedocs`. ([#2557], [#2562])
 * Admonitions with category `todo` are now colored purple. Previously they were default-colored like all other unknown admonitions categories. ([#2526])
+* A `checkdocs_ignored_modules` keyword argument to `makedocs(...)`, which prevents `checkdocs` from warning about missing documentation in certain modules. ([#2233])
 
 ### Changed
 
@@ -1821,6 +1822,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 [#2216]: https://github.com/JuliaDocs/Documenter.jl/issues/2216
 [#2217]: https://github.com/JuliaDocs/Documenter.jl/issues/2217
 [#2232]: https://github.com/JuliaDocs/Documenter.jl/issues/2232
+[#2233]: https://github.com/JuliaDocs/Documenter.jl/issues/2233
 [#2236]: https://github.com/JuliaDocs/Documenter.jl/issues/2236
 [#2237]: https://github.com/JuliaDocs/Documenter.jl/issues/2237
 [#2245]: https://github.com/JuliaDocs/Documenter.jl/issues/2245
diff --git a/src/documents.jl b/src/documents.jl
index 1638b02aaf..05e9cf6b89 100644
--- a/src/documents.jl
+++ b/src/documents.jl
@@ -314,6 +314,7 @@ struct User
     linkcheck_timeout::Real   # ..but only wait this many seconds for each one.
     linkcheck_useragent::String  # User agent to use for linkchecks.
     checkdocs::Symbol         # Check objects missing from `@docs` blocks. `:none`, `:exports`, or `:all`.
+    checkdocs_ignored_modules::Vector{Module}  # ..and then ignore (some of) them.
     doctestfilters::Vector{Regex} # Filtering for doctests
     warnonly::Vector{Symbol}  # List of docerror groups that should only warn, rather than cause a build failure
     pages   :: Vector{Any}    # Ordering of document pages specified by the user.
@@ -388,6 +389,7 @@ function Document(;
         linkcheck_timeout :: Real    = 10,
         linkcheck_useragent :: String= _LINKCHECK_DEFAULT_USERAGENT,
         checkdocs::Symbol            = :all,
+        checkdocs_ignored_modules::Vector{Module} = Module[],
         doctestfilters::Vector{Regex}= Regex[],
         warnonly :: Union{Bool,Symbol,Vector{Symbol}} = Symbol[],
         modules  :: Union{Module, Vector{Module}} = Module[],
@@ -454,6 +456,7 @@ function Document(;
         linkcheck_timeout,
         linkcheck_useragent,
         checkdocs,
+        checkdocs_ignored_modules,
         doctestfilters,
         warnonly,
         pages,
@@ -494,7 +497,7 @@ function Document(;
 
     blueprint = DocumentBlueprint(
         Dict{String, Page}(),
-        submodules(modules),
+        submodules(modules; ignore=Set(checkdocs_ignored_modules)),
     )
     Document(user, internal, plugin_dict, blueprint)
 end
diff --git a/src/makedocs.jl b/src/makedocs.jl
index 33f4893618..dc3d44e737 100644
--- a/src/makedocs.jl
+++ b/src/makedocs.jl
@@ -178,7 +178,15 @@ are `:all` (check all names; the default), `:exports` (check only exported names
 `:none` (no checks are performed).
 
 By default, if the document check detect any errors, it will fail the documentation build.
-This behavior can be relaxed with the `warnonly` keyword.
+This behavior can be relaxed with the `warnonly` or `checkdocs_ignored_modules` keywords.
+
+**`checkdocs_ignored_modules`** prevents `checkdocs` from checking modules supplied as a list
+of module objects. It will also cause all submodules of these module to be ignored. It can be
+useful for completely private modules including modules which have been vendored from
+elsewhere.
+
+Note that `checkdocs_ignored_modules` does not conversely verify that these docstrings are *not*
+included in the documentation.
 
 **`linkcheck`** -- if set to `true` [`makedocs`](@ref) uses `curl` to check the status codes
 of external-pointing links, to make sure that they are up-to-date. The links and their
diff --git a/src/utilities/utilities.jl b/src/utilities/utilities.jl
index 1abbdb337e..66c2307fc0 100644
--- a/src/utilities/utilities.jl
+++ b/src/utilities/utilities.jl
@@ -201,19 +201,19 @@ end
 """
 Returns the set of submodules of a given root module/s.
 """
-function submodules(modules::Vector{Module})
+function submodules(modules::Vector{Module}; ignore = Set{Module}())
     out = Set{Module}()
     for each in modules
-        submodules(each, out)
+        submodules(each, out; ignore=ignore)
     end
     out
 end
-function submodules(root::Module, seen = Set{Module}())
+function submodules(root::Module, seen = Set{Module}(); ignore = Set{Module}())
     push!(seen, root)
     for name in names(root, all=true)
         if Base.isidentifier(name) && isdefined(root, name) && !isdeprecated(root, name)
             object = getfield(root, name)
-            if isa(object, Module) && !(object in seen) && parentmodule(object::Module) == root
+            if isa(object, Module) && !(object in seen) && !(object in ignore) && parentmodule(object::Module) == root
                 submodules(object, seen)
             end
         end
diff --git a/test/missingdocs/make.jl b/test/missingdocs/make.jl
index 4399ea2aa9..40be86e1bf 100644
--- a/test/missingdocs/make.jl
+++ b/test/missingdocs/make.jl
@@ -13,6 +13,15 @@ module MissingDocs
     g(x) = x
 end
 
+module MissingDocsSubmodule
+    module UndocumentedSubmodule
+        export f
+
+        "exported"
+        f(x) = x
+    end
+end
+
 @testset "missing docs" begin
     for (sym, n_expected) in zip([:none, :exports, :all], [0, 1, 2])
         kwargs = (
@@ -38,6 +47,23 @@ end
         checkdocs = :all,
         sitename = "MissingDocs Checks",
     )
+
+    for (ignore, n_expected) in zip([false, true] , [1, 0])
+        kwargs = (
+            root = dirname(@__FILE__),
+            source = joinpath("src", "none"),
+            build = joinpath("build", "submodule"),
+            modules = MissingDocsSubmodule,
+            checkdocs = :all,
+            sitename = "MissingDocsSubmodule Checks",
+            warnonly = true,
+            checkdocs_ignored_modules = ignore ? Module[MissingDocsSubmodule.UndocumentedSubmodule] : Module[],
+        )
+        @quietly @test makedocs(; kwargs...) === nothing
+
+        doc = Documenter.Document(; kwargs...)
+        @quietly @test Documenter.missingdocs(doc) == n_expected
+    end
 end
 
 end