diff --git a/src/deploydocs.jl b/src/deploydocs.jl
index e33dfde922..a45dc734a8 100644
--- a/src/deploydocs.jl
+++ b/src/deploydocs.jl
@@ -273,7 +273,10 @@ function deploydocs(;
                 inventory_version = _get_inventory_version(objects_inv)
                 deploy_version = _get_deploy_version(deploy_subfolder)
                 if !isempty(deploy_version) && (inventory_version != deploy_version)
-                    error("Inventory declares version `$inventory_version`, but `deploydocs` is for version `$deploy_version`")
+                    if !isempty(inventory_version)
+                        @warn "Inventory declares version `$inventory_version`, but `deploydocs` is for version `$deploy_version`. Overwriting inventory version."
+                    end
+                    _patch_inventory_version(objects_inv, deploy_version)
                 end
             end
             @debug "pushing new documentation to remote: '$deploy_repo:$deploy_branch'."
@@ -303,6 +306,23 @@ function _get_inventory_version(objects_inv)
 end
 
 
+function _patch_inventory_version(objects_inv, version)
+    objects_inv_patched = tempname()
+    open(objects_inv) do input
+        open(objects_inv_patched, "w") do output
+            for line in eachline(input; keep=true)
+                if startswith(line, "# Version:")
+                    @debug "Patched $objects_inv with version=$version"
+                    line = "# Version: $version\n"
+                end
+                write(output, line)
+            end
+        end
+    end
+    mv(objects_inv_patched, objects_inv; force=true)
+end
+
+
 function _get_deploy_version(foldername)
     try
         return string(VersionNumber(foldername))  # strips the leading "v" from foldername
diff --git a/src/html/HTMLWriter.jl b/src/html/HTMLWriter.jl
index 7e9cce19a0..3bc80be668 100644
--- a/src/html/HTMLWriter.jl
+++ b/src/html/HTMLWriter.jl
@@ -55,7 +55,8 @@ The [format of the `objects.inv` file](https://juliadocs.org/DocInventories.jl/s
 is borrowed from the [Sphinx project](https://www.sphinx-doc.org/en/master/). It consists
 of a plain text header that includes the project name, taken from the `sitename` argument
 to [`Documenter.makedocs`](@ref), and a project `version` obtained from the closest
-`Project.toml` or `VERSION` file.
+`Project.toml`, `JuliaProject.toml`, or `VERSION` file that defines a `version`,
+respectively from the deployment tag in [`Documenter.deploydocs`](@ref).
 
 The bulk of the file is a list of plain text records, compressed with gzip. See
 [Inventory Generation](http://juliadocs.org/DocumenterInterLinks.jl/stable/write_inventory/)
diff --git a/test/deploydocs.jl b/test/deploydocs.jl
index 2bc71745da..7b5c1f862d 100644
--- a/test/deploydocs.jl
+++ b/test/deploydocs.jl
@@ -33,15 +33,6 @@ Documenter.authenticated_repo_url(c::TestDeployConfig) = c.repo_path
                 devbranch = "master",
             )
             # Deploy 1.0.0 tag
-            @test_throws ErrorException("Inventory declares version ``, but `deploydocs` is for version `1.0.0`") begin
-                deploydocs(
-                    root = pwd(),
-                    deploy_config = TestDeployConfig(full_repo_path, "1.0.0"),
-                    repo = full_repo_path,
-                    devbranch = "master",
-                )
-            end
-            DocInventories.save(objects_inv, Inventory(project="test", version="1.0.0"))
             @quietly deploydocs(
                 root = pwd(),
                 deploy_config = TestDeployConfig(full_repo_path, "1.0.0"),
@@ -49,15 +40,9 @@ Documenter.authenticated_repo_url(c::TestDeployConfig) = c.repo_path
                 devbranch = "master",
             )
             # Deploy 1.1.0 tag
-            @test_throws ErrorException("Inventory declares version `1.0.0`, but `deploydocs` is for version `1.1.0`") begin
-                deploydocs(
-                    root = pwd(),
-                    deploy_config = TestDeployConfig(full_repo_path, "1.1.0"),
-                    repo = full_repo_path,
-                    devbranch = "master",
-                )
-            end
-            DocInventories.save(objects_inv, Inventory(project="test", version="1.1.0"))
+            # (note that the inventory still declares 1.0.0 as the version, so
+            # this implicitly tests that `deploydocs` overwrites it with the
+            # correct version)
             @quietly deploydocs(
                 root = pwd(),
                 deploy_config = TestDeployConfig(full_repo_path, "1.1.0"),