diff --git a/CHANGELOG.markdown b/CHANGELOG.markdown
new file mode 100644
index 0000000000000000000000000000000000000000..e8d7a5002425c96242ebcddd1fd6cb5d87c287ff
--- /dev/null
+++ b/CHANGELOG.markdown
@@ -0,0 +1,3 @@
+2.1.3
+-----
+* Removed the now-irrelevant `Error` constraint from the `MonadError` instance for `Either e`.
diff --git a/mtl.cabal b/mtl.cabal
index 730f8641ea0a9e87e5a079a9743c1dda3456712e..3deab7ca751ab95ca64c0b7ec16f6a0aebe4bcd6 100644
--- a/mtl.cabal
+++ b/mtl.cabal
@@ -16,6 +16,7 @@ description:
     by Mark P Jones, in /Advanced School of Functional Programming/, 1995
     (<http://web.cecs.pdx.edu/~mpj/pubs/springschool.html>).
 build-type: Simple
+extra-source-files: CHANGELOG.markdown
 
 source-repository head
   type: git