diff --git a/altair/__init__.py b/altair/__init__.py
index 8d55814b9..1111e8188 100644
--- a/altair/__init__.py
+++ b/altair/__init__.py
@@ -1,5 +1,5 @@
 # ruff: noqa
-__version__ = "5.1.0dev"
+__version__ = "5.1.0"
 
 from typing import Any
 
diff --git a/doc/conf.py b/doc/conf.py
index 78a4b7a1a..76776b448 100644
--- a/doc/conf.py
+++ b/doc/conf.py
@@ -76,7 +76,7 @@
 # built documents.
 #
 # The short X.Y version.
-version = "5.1.0dev"
+version = "5.1.0"
 # The full version, including alpha/beta/rc tags.
 release = f"{version}"
 
diff --git a/doc/releases/changes.rst b/doc/releases/changes.rst
index 4a8119c6e..894a8f1d6 100644
--- a/doc/releases/changes.rst
+++ b/doc/releases/changes.rst
@@ -3,7 +3,7 @@
 Release Notes
 =============
 
-Version 5.1.0 (unreleased month date, year)
+Version 5.1.0 (released August 28, 2023)
 -------------------------------------------
 
 - Update Vega-Lite from version 5.8.0 to version 5.14.1;