diff --git a/History.markdown b/History.markdown
index f70a5e710..94a5303da 100644
--- a/History.markdown
+++ b/History.markdown
@@ -1,4 +1,4 @@
-## HEAD
+## 4.2.1 / 2021-09-27
 
 ### Bug Fixes
 
diff --git a/lib/jekyll/version.rb b/lib/jekyll/version.rb
index 1b23b987f..f6cd7eddf 100644
--- a/lib/jekyll/version.rb
+++ b/lib/jekyll/version.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
 
 module Jekyll
-  VERSION = "4.2.0"
+  VERSION = "4.2.1"
 end