diff -up ./Doc/conf.py.bak ./Doc/conf.py
--- ./Doc/conf.py.bak	2018-10-27 23:08:03.000000000 +0200
+++ ./Doc/conf.py	2018-11-17 15:34:58.392588884 +0100
@@ -20,6 +20,10 @@ print sys.path
 # Mock existence of native modules
 from Crypto.Util import _raw_api
 
+from distutils.version import LooseVersion
+
+import sphinx
+
 class MockLib(object):
     ghash_portable = None
     ghash_expand_portable = None
@@ -40,7 +44,11 @@ _raw_api.load_pycryptodome_raw_lib = lam
 
 # Add any Sphinx extension module names here, as strings. They can be extensions
 # coming with Sphinx (named 'sphinx.ext.*') or your custom ones.
-extensions = [ 'sphinx.ext.autodoc', 'sphinx.ext.napoleon',
+if LooseVersion(sphinx.__version__) <= LooseVersion('1.2'):
+    napoleon_ext = 'sphinxcontrib.napoleon'
+else:
+    napoleon_ext = 'sphinx.ext.napoleon'
+extensions = [ 'sphinx.ext.autodoc', napoleon_ext,
         'sphinx.ext.mathjax' ]
 
 # Add any paths that contain templates here, relative to this directory.