diff --git a/src/pydocstyle/config.py b/src/pydocstyle/config.py
index e1fbc0a9..60d11f00 100644
--- a/src/pydocstyle/config.py
+++ b/src/pydocstyle/config.py
@@ -463,7 +463,7 @@ def _expand_error_codes(code_parts):
                         'known errors: %s', part)
                 expanded_codes.update(codes_to_add)
         except TypeError as e:
-            raise IllegalConfiguration(e)
+            raise IllegalConfiguration(e) from e
 
         return expanded_codes