diff --git a/.circleci/config.yml b/.circleci/config.yml
index 9fa60607fe..5bba79b618 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -3,7 +3,7 @@ version: 2
 jobs:
   backend:
     docker:
-      - image: cimg/python:3.8.11
+      - image: cimg/python:3.12
     environment:
       PIPENV_VENV_IN_PROJECT: true
     steps:
@@ -62,7 +62,7 @@ jobs:
 
   ui_tests:
     docker:
-      - image: cimg/python:3.8.11-browsers
+      - image: cimg/python:3.12-browsers
     environment:
       PIPENV_VENV_IN_PROJECT: true
       DJANGO_SETTINGS_MODULE: wagtail.test.settings_ui
@@ -118,7 +118,7 @@ jobs:
 
   nightly-build:
     docker:
-      - image: cimg/python:3.8.11-node
+      - image: cimg/python:3.12-node
     steps:
       - checkout
       - run: pip install --user wheel boto3
diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index b702185b60..3e6e6a44bf 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -20,7 +20,7 @@ concurrency:
 # - test runs with USE_EMAIL_USER_MODEL=yes and DISABLE_TIMEZONE=yes
 
 # Current configuration:
-# - django 4.2, python 3.8, postgres:12, parallel
+# - django 4.2, python 3.9, postgres:12, parallel
 # - django 4.2, python 3.9, mysql:8.0
 # - django 4.2, python 3.10, sqlite
 # - django 5.0, python 3.12, mysql:8.1, parallel
@@ -28,7 +28,7 @@ concurrency:
 # - django 5.0, python 3.12, postgres:15, parallel, DISABLE_TIMEZONE=yes
 # - django stable/5.1.x, python 3.11, postgres:15 (allow failures)
 # - django main, python 3.12, postgres:latest, parallel (allow failures)
-# - elasticsearch 7, django 4.2, python 3.8, postgres:latest
+# - elasticsearch 7, django 4.2, python 3.9, postgres:latest
 # - opensearch 2, django 4.2, python 3.9, sqlite
 # - elasticsearch 8, django 5.0, python 3.11, sqlite, USE_EMAIL_USER_MODEL=yes
 
@@ -80,7 +80,7 @@ jobs:
     strategy:
       matrix:
         include:
-          - python: '3.8'
+          - python: '3.9'
             django: 'Django>=4.2,<4.3'
             experimental: false
             parallel: '--parallel'
@@ -249,7 +249,7 @@ jobs:
     strategy:
       matrix:
         include:
-          - python: '3.8'
+          - python: '3.9'
             django: 'Django>=4.2,<4.3'
             experimental: false
 
diff --git a/README.md b/README.md
index cbcf322f98..e3b2f3b147 100644
--- a/README.md
+++ b/README.md
@@ -92,10 +92,10 @@ _(If you are reading this on GitHub, the details here may not be indicative of t
 Wagtail supports:
 
 -   Django 4.2.x and 5.0.x
--   Python 3.8, 3.9, 3.10, 3.11 and 3.12
+-   Python 3.9, 3.10, 3.11 and 3.12
 -   PostgreSQL, MySQL and SQLite (with JSON1) as database backends
 
-[Previous versions of Wagtail](https://docs.wagtail.org/en/stable/releases/upgrading.html#compatible-django-python-versions) additionally supported Python 2.7, 3.7 and earlier Django versions.
+[Previous versions of Wagtail](https://docs.wagtail.org/en/stable/releases/upgrading.html#compatible-django-python-versions) additionally supported Python 2.7, 3.8 and earlier Django versions.
 
 ---
 
diff --git a/docs/getting_started/tutorial.md b/docs/getting_started/tutorial.md
index 1bcf23412e..e9a38bcce1 100644
--- a/docs/getting_started/tutorial.md
+++ b/docs/getting_started/tutorial.md
@@ -24,7 +24,7 @@ python3 --version
 py --version
 ```
 
-If none of the preceding commands return a version number, or return a version lower than 3.8, then [install Python 3](https://www.python.org/downloads/).
+If none of the preceding commands return a version number, or return a version lower than 3.9, then [install Python 3](https://www.python.org/downloads/).
 
 (virtual_environment_creation)=
 
diff --git a/docs/releases/6.3.md b/docs/releases/6.3.md
index 77103f762d..bfc44dcb41 100644
--- a/docs/releases/6.3.md
+++ b/docs/releases/6.3.md
@@ -32,6 +32,10 @@ depth: 1
 
 ## Upgrade considerations - deprecation of old functionality
 
+### Removed support for Python 3.8
+
+Python 3.8 is no longer supported as of this release; please upgrade to Python 3.9 or above before upgrading Wagtail.
+
 ## Upgrade considerations - changes affecting Wagtail customisations
 
 ## Upgrade considerations - changes to undocumented internals
diff --git a/docs/releases/upgrading.md b/docs/releases/upgrading.md
index c186e41aee..ad8c923cc8 100644
--- a/docs/releases/upgrading.md
+++ b/docs/releases/upgrading.md
@@ -59,7 +59,7 @@ The compatible versions of Django and Python for each Wagtail release are:
 
 | Wagtail release | Compatible Django versions | Compatible Python versions |
 | --------------- | -------------------------- | -------------------------- |
-| 6.3             | 4.2, 5.0                   | 3.8, 3.9, 3.10, 3.11, 3.12 |
+| 6.3             | 4.2, 5.0                   | 3.9, 3.10, 3.11, 3.12      |
 | 6.2             | 4.2, 5.0                   | 3.8, 3.9, 3.10, 3.11, 3.12 |
 | 6.1             | 4.2, 5.0                   | 3.8, 3.9, 3.10, 3.11, 3.12 |
 | 6.0             | 4.2, 5.0                   | 3.8, 3.9, 3.10, 3.11, 3.12 |
diff --git a/setup.py b/setup.py
index 8ead614ecf..7cc01246a3 100755
--- a/setup.py
+++ b/setup.py
@@ -108,7 +108,6 @@ https://github.com/wagtail/wagtail/.",
         "Operating System :: OS Independent",
         "Programming Language :: Python",
         "Programming Language :: Python :: 3",
-        "Programming Language :: Python :: 3.8",
         "Programming Language :: Python :: 3.9",
         "Programming Language :: Python :: 3.10",
         "Programming Language :: Python :: 3.11",
@@ -119,7 +118,7 @@ https://github.com/wagtail/wagtail/.",
         "Framework :: Wagtail",
         "Topic :: Internet :: WWW/HTTP :: Site Management",
     ],
-    python_requires=">=3.8",
+    python_requires=">=3.9",
     install_requires=install_requires,
     extras_require={"testing": testing_extras, "docs": documentation_extras},
     entry_points="""
diff --git a/tox.ini b/tox.ini
index d13ff719b5..bb276aa83c 100644
--- a/tox.ini
+++ b/tox.ini
@@ -2,7 +2,7 @@
 skipsdist = True
 usedevelop = True
 
-envlist = py{38,39,310,311,312}-dj{42,50,50stable,main}-{sqlite,postgres,mysql,mssql}-{elasticsearch8,elasticsearch7,noelasticsearch}-{customuser,emailuser}-{tz,notz},
+envlist = py{39,310,311,312}-dj{42,50,50stable,main}-{sqlite,postgres,mysql,mssql}-{elasticsearch8,elasticsearch7,noelasticsearch}-{customuser,emailuser}-{tz,notz},
 
 [testenv]
 install_command = pip install -e ".[testing]" -U {opts} {packages}
@@ -12,7 +12,6 @@ commands =
     noelasticsearch: coverage run runtests.py {posargs}
 
 basepython =
-    py38: python3.8
     py39: python3.9
     py310: python3.10
     py311: python3.11
diff --git a/wagtail/project_template/Dockerfile b/wagtail/project_template/Dockerfile
index 6cb4148df4..97dd7dfc3d 100644
--- a/wagtail/project_template/Dockerfile
+++ b/wagtail/project_template/Dockerfile
@@ -1,5 +1,5 @@
-# Use an official Python runtime based on Debian 10 "buster" as a parent image.
-FROM python:3.8.1-slim-buster
+# Use an official Python runtime based on Debian 12 "bookworm" as a parent image.
+FROM python:3.12-slim-bookworm
 
 # Add user that will be used in the container.
 RUN useradd wagtail