diff --git a/src/wp-admin/includes/update-core.php b/src/wp-admin/includes/update-core.php
index 32664bf6ff..e411b817dc 100644
--- a/src/wp-admin/includes/update-core.php
+++ b/src/wp-admin/includes/update-core.php
@@ -864,6 +864,7 @@ $_new_bundled_files = array(
 	'themes/twentynineteen/'  => '5.0',
 	'themes/twentytwenty/'    => '5.3',
 	'themes/twentytwentyone/' => '5.6',
+	'themes/twentytwentytwo/' => '5.9',
 );
 
 /**
diff --git a/src/wp-includes/class-wp-theme.php b/src/wp-includes/class-wp-theme.php
index d0607528b5..6b7ddc8e26 100644
--- a/src/wp-includes/class-wp-theme.php
+++ b/src/wp-includes/class-wp-theme.php
@@ -70,6 +70,7 @@ final class WP_Theme implements ArrayAccess {
 		'twentynineteen'  => 'Twenty Nineteen',
 		'twentytwenty'    => 'Twenty Twenty',
 		'twentytwentyone' => 'Twenty Twenty-One',
+		'twentytwentytwo' => 'Twenty Twenty-Two',
 	);
 
 	/**
diff --git a/src/wp-includes/default-constants.php b/src/wp-includes/default-constants.php
index 21a855ad25..cd70ca5cf6 100644
--- a/src/wp-includes/default-constants.php
+++ b/src/wp-includes/default-constants.php
@@ -409,7 +409,7 @@ function wp_templating_constants() {
 	 * @see WP_Theme::get_core_default_theme()
 	 */
 	if ( ! defined( 'WP_DEFAULT_THEME' ) ) {
-		define( 'WP_DEFAULT_THEME', 'twentytwentyone' );
+		define( 'WP_DEFAULT_THEME', 'twentytwentytwo' );
 	}
 
 }
diff --git a/tests/phpunit/tests/theme.php b/tests/phpunit/tests/theme.php
index 6c495ed023..32ca5dae36 100644
--- a/tests/phpunit/tests/theme.php
+++ b/tests/phpunit/tests/theme.php
@@ -20,6 +20,7 @@ class Tests_Theme extends WP_UnitTestCase {
 		'twentynineteen',
 		'twentytwenty',
 		'twentytwentyone',
+		'twentytwentytwo',
 	);
 
 	public function set_up() {