From 4a7c269357548019e7794e6d933e7a0805d92e10 Mon Sep 17 00:00:00 2001
From: Thomas Li <47963215+lithomas1@users.noreply.github.com>
Date: Sat, 30 Dec 2023 07:33:00 -0800
Subject: [PATCH] Backport PR #56312: DOC: Add whatsnew for concat regression

---
 doc/source/whatsnew/v2.2.0.rst | 1 +
 1 file changed, 1 insertion(+)

diff --git a/doc/source/whatsnew/v2.2.0.rst b/doc/source/whatsnew/v2.2.0.rst
index 129f5cedb86c2..649ad37a56b35 100644
--- a/doc/source/whatsnew/v2.2.0.rst
+++ b/doc/source/whatsnew/v2.2.0.rst
@@ -761,6 +761,7 @@ Datetimelike
 - Bug in parsing datetime strings with nanosecond resolution with non-ISO8601 formats incorrectly truncating sub-microsecond components (:issue:`56051`)
 - Bug in parsing datetime strings with sub-second resolution and trailing zeros incorrectly inferring second or millisecond resolution (:issue:`55737`)
 - Bug in the results of :func:`to_datetime` with an floating-dtype argument with ``unit`` not matching the pointwise results of :class:`Timestamp` (:issue:`56037`)
+- Fixed regression where :func:`concat` would raise an error when concatenating ``datetime64`` columns with differing resolutions (:issue:`53641`)
 
 Timedelta
 ^^^^^^^^^