diff --git a/oslo_cache/core.py b/oslo_cache/core.py
index 0374e533..4e1ade0d 100644
--- a/oslo_cache/core.py
+++ b/oslo_cache/core.py
@@ -140,16 +140,16 @@ def _sha1_mangle_key(key):
     return util.sha1_mangle_key(key)
 
 
-def configure_cache_region(region, conf):
+def configure_cache_region(conf, region):
     """Configure a cache region.
 
     If the cache region is already configured, this function does nothing.
     Otherwise, the region is configured.
 
-    :param region: Cache region to configure
-    :type region: dogpile.cache.CacheRegion
     :param conf: config object, must have had :func:`configure` called on it.
     :type conf: oslo_config.cfg.ConfigOpts
+    :param region: Cache region to configure
+    :type region: dogpile.cache.CacheRegion
     :raises oslo_cache.exception.ConfigurationError: If the region parameter is
         not a dogpile.cache.CacheRegion.
     :returns: The region.
diff --git a/oslo_cache/tests/test_cache.py b/oslo_cache/tests/test_cache.py
index a9b88d7b..89c9227e 100644
--- a/oslo_cache/tests/test_cache.py
+++ b/oslo_cache/tests/test_cache.py
@@ -95,7 +95,7 @@ class CacheRegionTest(BaseTestCase):
     def setUp(self):
         super(CacheRegionTest, self).setUp()
         self.region = cache._make_region()
-        cache.configure_cache_region(self.region, self.config_fixture.conf)
+        cache.configure_cache_region(self.config_fixture.conf, self.region)
         self.region.wrap(TestProxy)
         self.test_value = TestProxyValue('Decorator Test')
 
@@ -130,8 +130,8 @@ class CacheRegionTest(BaseTestCase):
 
     def test_cache_region_no_error_multiple_config(self):
         # Verify configuring the CacheRegion again doesn't error.
-        cache.configure_cache_region(self.region, self.config_fixture.conf)
-        cache.configure_cache_region(self.region, self.config_fixture.conf)
+        cache.configure_cache_region(self.config_fixture.conf, self.region)
+        cache.configure_cache_region(self.config_fixture.conf, self.region)
 
     def _get_cache_fallthrough_fn(self, cache_time):
         with mock.patch.object(cache.REGION, 'cache_on_arguments',
@@ -347,7 +347,7 @@ class CacheNoopBackendTest(BaseTestCase):
                                    backend='oslo_cache.noop')
 
         self.region = cache._make_region()
-        cache.configure_cache_region(self.region, self.config_fixture.conf)
+        cache.configure_cache_region(self.config_fixture.conf, self.region)
 
     def test_noop_backend(self):
         single_value = 'Test Value'