Preparing release v1.2.0 (#29)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index dcb73b6..f1b852c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,7 +1,7 @@
 Releases
 ========
 
-v1.2.0 (unreleased)
+v1.2.0 (2019-09-26)
 ===================
 
 -   Support extracting and matching against wrapped errors with `errors.As`