diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 293d3e4de6e..b4804d01ad0 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -23,6 +23,7 @@ env:
   FORCE_COLOR: "1"
   PYTHONDEVMODE: "1"  # -X dev
   PYTHONWARNDEFAULTENCODING: "1"  # -X warn_default_encoding
+  UV_SYSTEM_PYTHON: "1"  # make uv do global installs
 
 jobs:
   ubuntu:
@@ -124,6 +125,38 @@ jobs:
         DO_EPUBCHECK: "1"
         EPUBCHECK_PATH: "/tmp/epubcheck/epubcheck-5.1.0/epubcheck.jar"
 
+  oldest-supported:
+    runs-on: ubuntu-latest
+    name: Oldest supported
+
+    steps:
+    - uses: actions/checkout@v4
+    - name: Set up Python
+      uses: actions/setup-python@v5
+      with:
+        python-version: "3"
+    - name: Check Python version
+      run: python --version --version
+    - name: Install graphviz
+      run: sudo apt-get install graphviz
+    - name: Install uv
+      run: > 
+        curl 
+        --location 
+        --fail
+        --proto '=https' --tlsv1.2 
+        --silent --show-error 
+        https://astral.sh/uv/install.sh
+        | sh
+    - name: Install dependencies
+      run: |
+        uv pip install .[test] --resolution lowest-direct
+        uv pip install alabaster==1.0.0
+    - name: Test with pytest
+      run: python -m pytest -vv --durations 25
+      env:
+        PYTHONWARNINGS: "error"  # treat all warnings as errors
+
   latex:
     runs-on: ubuntu-latest
     name: LaTeX
diff --git a/CHANGES.rst b/CHANGES.rst
index c629a6d9a55..99fc230cdad 100644
--- a/CHANGES.rst
+++ b/CHANGES.rst
@@ -4,6 +4,9 @@ Release 8.1.0 (in development)
 Dependencies
 ------------
 
+* #12756: Add lower-bounds to the ``sphinxcontrib-*`` dependencies.
+  Patch by Adam Turner.
+
 Incompatible changes
 --------------------
 
diff --git a/pyproject.toml b/pyproject.toml
index 752769377d2..ff26246c2a9 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -55,12 +55,12 @@ classifiers = [
     "Topic :: Utilities",
 ]
 dependencies = [
-    "sphinxcontrib-applehelp",
-    "sphinxcontrib-devhelp",
-    "sphinxcontrib-jsmath",
-    "sphinxcontrib-htmlhelp>=2.0.0",
+    "sphinxcontrib-applehelp>=1.0.7",
+    "sphinxcontrib-devhelp>=1.0.6",
+    "sphinxcontrib-htmlhelp>=2.0.6",
+    "sphinxcontrib-jsmath>=1.0.1",
+    "sphinxcontrib-qthelp>=1.0.6",
     "sphinxcontrib-serializinghtml>=1.1.9",
-    "sphinxcontrib-qthelp",
     "Jinja2>=3.1",
     "Pygments>=2.17",
     "docutils>=0.20,<0.22",