diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 88d6340c5..9cc469caa 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -13,17 +13,16 @@ jobs:
       max-parallel: 5
       matrix:
         python-version:
-        - "3.6"
-        - "3.7"
-        - "3.8"
         - "3.9"
         - "3.10"
         - "3.11"
+        - "3.12"
+        - "3.13"
         - "pypy3.9"
 
     steps:
     - uses: actions/checkout@v2
-    - uses: actions/setup-python@v4
+    - uses: actions/setup-python@v5
       with:
         python-version: ${{ matrix.python-version }}
     - name: Install tox
diff --git a/CHANGELOG.rst b/CHANGELOG.rst
index e1dbcf80a..e1b8ef195 100644
--- a/CHANGELOG.rst
+++ b/CHANGELOG.rst
@@ -1,6 +1,26 @@
 Release History
 ===============
 
+dev
+---
+
+**API Changes (Backward Incompatible)**
+
+- Support for Python 3.6 has been removed.
+- Support for Python 3.7 has been removed.
+- Support for Python 3.8 has been removed.
+
+**API Changes (Backward Compatible)**
+
+- Support for Python 3.11 has been added.
+- Support for Python 3.12 has been added.
+- Support for Python 3.13 has been added.
+- Added typing information.
+
+**Bugfixes**
+
+-
+
 4.1.0 (2021-10-05)
 ------------------
 
diff --git a/setup.py b/setup.py
index 979f0de82..6a49b2274 100644
--- a/setup.py
+++ b/setup.py
@@ -31,7 +31,7 @@
     packages=find_packages(where="src"),
     package_data={'h2': []},
     package_dir={'': 'src'},
-    python_requires='>=3.6.1',
+    python_requires='>=3.9.0',
     license='MIT License',
     classifiers=[
         'Development Status :: 5 - Production/Stable',
@@ -39,12 +39,11 @@
         'License :: OSI Approved :: MIT License',
         'Programming Language :: Python',
         'Programming Language :: Python :: 3',
-        'Programming Language :: Python :: 3.6',
-        'Programming Language :: Python :: 3.7',
-        'Programming Language :: Python :: 3.8',
         'Programming Language :: Python :: 3.9',
         'Programming Language :: Python :: 3.10',
         'Programming Language :: Python :: 3.11',
+        'Programming Language :: Python :: 3.12',
+        'Programming Language :: Python :: 3.13',
         'Programming Language :: Python :: Implementation :: CPython',
         'Programming Language :: Python :: Implementation :: PyPy',
     ],
diff --git a/tox.ini b/tox.ini
index eaf0a4360..16e786fb4 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,14 +1,13 @@
 [tox]
-envlist = py36, py37, py38, py39, py310, py311, pypy3, lint, docs, packaging
+envlist = py39, py310, py311, py312, py13, pypy3, lint, docs, packaging
 
 [gh-actions]
 python =
-    3.6: py36
-    3.7: py37
-    3.8: py38
     3.9: py39, lint, docs, packaging, h2spec
     3.10: py310
     3.11: py311
+    3.12: py312
+    3.13: py313
     pypy3: pypy3
 
 [testenv]
@@ -33,7 +32,7 @@ commands = flake8 src/ test/
 
 [testenv:docs]
 deps =
-    sphinx>=5.0.2,<6
+    sphinx>=7.4.7,<9
 allowlist_externals = make
 changedir = {toxinidir}/docs
 commands =
@@ -43,9 +42,9 @@ commands =
 [testenv:packaging]
 basepython = python3.9
 deps =
-    check-manifest==0.49
-    readme-renderer==37.3
-    twine>=3.4.1,<4
+    check-manifest==0.50
+    readme-renderer==44.0
+    twine>=5.1.1,<6
 allowlist_externals = rm
 commands =
     rm -rf dist/
@@ -63,14 +62,14 @@ commands =
     twine upload dist/*
 
 [testenv:graphs]
-basepython = python3.8
+basepython = python3.9
 deps =
     graphviz==0.14.1
 commands =
     python visualizer/visualize.py -i docs/source/_static
 
 [testenv:h2spec]
-basepython = python3.8
+basepython = python3.9
 deps =
     twisted[tls]==20.3.0
 allowlist_externals = {toxinidir}/test/h2spectest.sh