diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 91d87f6c..3e62215c 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -8,7 +8,7 @@ jobs:
     strategy:
       matrix:
         os: [macos-latest, ubuntu-latest, windows-latest]
-        python-version: [3.5, 3.6, 3.7, 3.8, 3.9-dev]
+        python-version: [3.6, 3.7, 3.8, 3.9-dev]
 
     steps:
     - uses: actions/checkout@v2
diff --git a/README.rst b/README.rst
index 088b5f01..179345d4 100644
--- a/README.rst
+++ b/README.rst
@@ -22,7 +22,7 @@ docstring conventions.
 `PEP 257 <http://www.python.org/dev/peps/pep-0257/>`_ out of the box, but it
 should not be considered a reference implementation.
 
-**pydocstyle** supports Python 3.5, 3.6, 3.7 and 3.8.
+**pydocstyle** supports Python 3.6, 3.7 and 3.8.
 
 
 Quick Start
diff --git a/docs/conf.py b/docs/conf.py
index 05583dac..6f6412a5 100644
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -1,5 +1,3 @@
-# -*- coding: utf-8 -*-
-#
 # pydocstyle documentation build configuration file, created by
 # sphinx-quickstart on Fri Jan 30 20:30:42 2015.
 #
diff --git a/docs/index.rst b/docs/index.rst
index dfe636ed..991a01e4 100644
--- a/docs/index.rst
+++ b/docs/index.rst
@@ -8,7 +8,7 @@ docstring conventions.
 `PEP 257 <http://www.python.org/dev/peps/pep-0257/>`_ out of the box, but it
 should not be considered a reference implementation.
 
-**pydocstyle** supports Python 3.5, 3.6, 3.7 and 3.8.
+**pydocstyle** supports Python 3.6, 3.7 and 3.8.
 
 
 .. include:: quickstart.rst
diff --git a/docs/release_notes.rst b/docs/release_notes.rst
index 45cf63af..52c55e16 100644
--- a/docs/release_notes.rst
+++ b/docs/release_notes.rst
@@ -8,6 +8,10 @@ Release Notes
 Current Development Version
 ---------------------------
 
+Major Updates
+
+* Support for Python 3.5 has been dropped (#510).
+
 New Features
 
 * Add flag to disable `# noqa` comment processing in API (#485).
diff --git a/setup.py b/setup.py
index 80369721..501afe3e 100644
--- a/setup.py
+++ b/setup.py
@@ -1,5 +1,4 @@
 from setuptools import setup
-import sys
 
 # Do not update the version manually - it is managed by `bumpversion`.
 version = '5.1.2rc'
@@ -24,14 +23,14 @@
         'Environment :: Console',
         'Development Status :: 5 - Production/Stable',
         'Programming Language :: Python :: 3',
-        'Programming Language :: Python :: 3.5',
         'Programming Language :: Python :: 3.6',
         'Programming Language :: Python :: 3.7',
         'Programming Language :: Python :: 3.8',
+        'Programming Language :: Python :: 3 :: Only',
         'Operating System :: OS Independent',
         'License :: OSI Approved :: MIT License',
     ],
-    python_requires='>=3.5',
+    python_requires='>=3.6',
     keywords='pydocstyle, PEP 257, pep257, PEP 8, pep8, docstrings',
     packages=('pydocstyle',),
     package_dir={'': 'src'},
@@ -43,6 +42,6 @@
         ],
     },
     project_urls={
-        'Release Notes': 'http://www.pydocstyle.org/en/latest/release_notes.html',
+        'Release Notes': 'https://www.pydocstyle.org/en/latest/release_notes.html',
     },
 )
diff --git a/src/pydocstyle/checker.py b/src/pydocstyle/checker.py
index 3cabc9a9..294a8ce2 100644
--- a/src/pydocstyle/checker.py
+++ b/src/pydocstyle/checker.py
@@ -385,23 +385,6 @@ def check_backslashes(self, definition, docstring):
                 and not docstring.startswith(('r', 'ur'))):
             return violations.D301()
 
-    @check_for(Definition)
-    def check_unicode_docstring(self, definition, docstring):
-        r'''D302: Use u""" for docstrings with Unicode.
-
-        For Unicode docstrings, use u"""Unicode triple-quoted strings""".
-
-        '''
-        if 'unicode_literals' in definition.module.future_imports:
-            return
-
-        # Just check that docstring is unicode, check_triple_double_quotes
-        # ensures the correct quotes.
-        if docstring and sys.version_info[0] <= 2:
-            if not is_ascii(docstring) and not docstring.startswith(
-                    ('u', 'ur')):
-                return violations.D302()
-
     @staticmethod
     def _check_ends_with(docstring, chars, violation):
         """First line ends with one of `chars`.
@@ -453,13 +436,7 @@ def check_imperative_mood(self, function, docstring):  # def context
                 if check_word in IMPERATIVE_BLACKLIST:
                     return violations.D401b(first_word)
 
-                try:
-                    correct_forms = IMPERATIVE_VERBS.get(stem(check_word))
-                except UnicodeDecodeError:
-                    # This is raised when the docstring contains unicode
-                    # characters in the first word, but is not a unicode
-                    # string. In which case D302 will be reported. Ignoring.
-                    return
+                correct_forms = IMPERATIVE_VERBS.get(stem(check_word))
 
                 if correct_forms and check_word not in correct_forms:
                     best = max(
@@ -985,7 +962,7 @@ def check(filenames, select=None, ignore=None, ignore_decorators=None, ignore_in
                 code = getattr(error, 'code', None)
                 if code in checked_codes:
                     yield error
-        except (EnvironmentError, AllError, ParseError) as error:
+        except (OSError, AllError, ParseError) as error:
             log.warning('Error in file %s: %s', filename, error)
             yield error
         except tk.TokenError:
diff --git a/src/pydocstyle/config.py b/src/pydocstyle/config.py
index 60d11f00..6e789d92 100644
--- a/src/pydocstyle/config.py
+++ b/src/pydocstyle/config.py
@@ -316,7 +316,7 @@ def _read_configuration_file(self, path):
                     continue
 
                 if opt.replace('_', '-') not in self.CONFIG_FILE_OPTIONS:
-                    log.warning("Unknown option '{}' ignored".format(opt))
+                    log.warning(f"Unknown option '{opt}' ignored")
                     continue
 
                 normalized_opt = opt.replace('-', '_')
@@ -335,7 +335,7 @@ def _read_configuration_file(self, path):
 
         if options is not None:
             if not self._validate_options(options):
-                raise IllegalConfiguration('in file: {}'.format(path))
+                raise IllegalConfiguration(f'in file: {path}')
 
         return options, should_inherit
 
@@ -388,7 +388,7 @@ def _create_check_config(cls, options, use_defaults=True):
 
         kwargs = dict(checked_codes=checked_codes)
         for key in ('match', 'match_dir', 'ignore_decorators'):
-            kwargs[key] = getattr(cls, 'DEFAULT_{}_RE'.format(key.upper())) \
+            kwargs[key] = getattr(cls, f'DEFAULT_{key.upper()}_RE') \
                 if getattr(options, key) is None and use_defaults \
                 else getattr(options, key)
         return CheckConfiguration(**kwargs)
@@ -521,7 +521,7 @@ def _get_set(value_str):
 
             """
             return cls._expand_error_codes(
-                set([x.strip() for x in value_str.split(",")]) - {""}
+                {x.strip() for x in value_str.split(",")} - {""}
             )
 
         for opt in optional_set_options:
diff --git a/src/pydocstyle/parser.py b/src/pydocstyle/parser.py
index 1b17c36c..a6afa863 100644
--- a/src/pydocstyle/parser.py
+++ b/src/pydocstyle/parser.py
@@ -55,7 +55,7 @@ def __eq__(self, other):
     def __repr__(self):
         kwargs = ', '.join('{}={!r}'.format(field, getattr(self, field))
                            for field in self._fields)
-        return '{}({})'.format(self.__class__.__name__, kwargs)
+        return f'{self.__class__.__name__}({kwargs})'
 
 
 class Definition(Value):
@@ -97,9 +97,9 @@ def is_empty_or_comment(line):
         return ''.join(reversed(list(filtered_src)))
 
     def __str__(self):
-        out = 'in {} {} `{}`'.format(self._publicity, self._human, self.name)
+        out = f'in {self._publicity} {self._human} `{self.name}`'
         if self.skipped_error_codes:
-            out += ' (skipping {})'.format(self.skipped_error_codes)
+            out += f' (skipping {self.skipped_error_codes})'
         return out
 
 
@@ -211,7 +211,7 @@ def is_public(self):
         # Check if we are a setter/deleter method, and mark as private if so.
         for decorator in self.decorators:
             # Given 'foo', match 'foo.bar' but not 'foobar' or 'sfoo'
-            if re(r"^{}\.".format(self.name)).match(decorator.name):
+            if re(fr"^{self.name}\.").match(decorator.name):
                 return False
         name_is_public = (not self.name.startswith('_') or
                           self.name in VARIADIC_MAGIC_METHODS or
@@ -343,7 +343,7 @@ def __init__(self, *args):
         self.kind = TokenKind(self.kind)
 
     def __str__(self):
-        return "{!r} ({})".format(self.kind, self.value)
+        return f"{self.kind!r} ({self.value})"
 
 
 class Parser:
@@ -472,8 +472,7 @@ def parse_definitions(self, class_, dunder_all=False):
                 yield self.parse_definition(class_._nest(self.current.value))
             elif self.current.kind == tk.INDENT:
                 self.consume(tk.INDENT)
-                for definition in self.parse_definitions(class_):
-                    yield definition
+                yield from self.parse_definitions(class_)
             elif self.current.kind == tk.DEDENT:
                 self.consume(tk.DEDENT)
                 return
diff --git a/src/pydocstyle/violations.py b/src/pydocstyle/violations.py
index 6515d3d6..f9f02f1e 100644
--- a/src/pydocstyle/violations.py
+++ b/src/pydocstyle/violations.py
@@ -52,10 +52,10 @@ def set_context(self, definition: Definition, explanation: str) -> None:
     @property
     def message(self) -> str:
         """Return the message to print to the user."""
-        ret = '{}: {}'.format(self.code, self.short_desc)
+        ret = f'{self.code}: {self.short_desc}'
         if self.context is not None:
             specific_error_msg = self.context.format(*self.parameters)
-            ret += ' ({})'.format(specific_error_msg)
+            ret += f' ({specific_error_msg})'
         return ret
 
     @property
@@ -69,7 +69,7 @@ def lines(self) -> str:
         lines_stripped = list(reversed(list(dropwhile(is_blank,
                                                       reversed(lines)))))
         numbers_width = len(str(offset + len(lines_stripped)))
-        line_format = '{{:{}}}:{{}}'.format(numbers_width)
+        line_format = f'{{:{numbers_width}}}:{{}}'
         for n, line in enumerate(lines_stripped):
             if line:
                 line = ' ' + line
@@ -159,7 +159,7 @@ def to_rst(cls) -> str:
         for group in cls.groups:
             table += sep_line
             table += blank_line
-            table += '|' + '**{}**'.format(group.name).center(max_len + 9) + '|\n'
+            table += '|' + f'**{group.name}**'.center(max_len + 9) + '|\n'
             table += blank_line
             for error in group.errors:
                 table += sep_line
@@ -214,7 +214,7 @@ def to_rst(cls) -> str:
 D300 = D3xx.create_error('D300', 'Use """triple double quotes"""',
                          'found {0}-quotes')
 D301 = D3xx.create_error('D301', 'Use r""" if any backslashes in a docstring')
-D302 = D3xx.create_error('D302', 'Use u""" for Unicode docstrings')
+D302 = D3xx.create_error('D302', 'Deprecated: Use u""" for Unicode docstrings')
 
 D4xx = ErrorRegistry.create_group('D4', 'Docstring Content Issues')
 D400 = D4xx.create_error('D400', 'First line should end with a period',
diff --git a/src/tests/parser_test.py b/src/tests/parser_test.py
index 05a329ec..061a3919 100644
--- a/src/tests/parser_test.py
+++ b/src/tests/parser_test.py
@@ -52,10 +52,6 @@ def do_something(pos_param0, pos_param1, kw_param0="default"):
 
 def test_simple_fstring():
     """Test parsing of a function with a simple fstring as a docstring."""
-    # fstrings are not supported in Python 3.5
-    if sys.version_info[0:2] == (3, 5):
-        return
-
     parser = Parser()
     code = CodeSnippet("""\
         def do_something(pos_param0, pos_param1, kw_param0="default"):
@@ -85,10 +81,6 @@ def do_something(pos_param0, pos_param1, kw_param0="default"):
 
 def test_fstring_with_args():
     """Test parsing of a function with an fstring with args as a docstring."""
-    # fstrings are not supported in Python 3.5
-    if sys.version_info[0:2] == (3, 5):
-        return
-
     parser = Parser()
     code = CodeSnippet("""\
         foo = "bar"
diff --git a/src/tests/test_cases/canonical_google_examples.py b/src/tests/test_cases/canonical_google_examples.py
index c219191f..301f83c4 100644
--- a/src/tests/test_cases/canonical_google_examples.py
+++ b/src/tests/test_cases/canonical_google_examples.py
@@ -83,7 +83,7 @@ def fetch_bigtable_rows(big_table, keys, other_silly_variable=None):
         "('Attributes', not 'Attributes:')")
 @expect("D407: Missing dashed underline after section ('Attributes')")
 @expect("D413: Missing blank line after last section ('Attributes')")
-class SampleClass(object):
+class SampleClass:
     """Summary of class here.
 
     Longer class information....
diff --git a/src/tests/test_cases/noqa.py b/src/tests/test_cases/noqa.py
index 7eeeac87..bbbc6a41 100644
--- a/src/tests/test_cases/noqa.py
+++ b/src/tests/test_cases/noqa.py
@@ -1,4 +1,3 @@
-# -*- coding: utf-8 -*-
 # noqa: D400,D415
 """Test case for "# noqa" comments"""
 from .expected import Expectation
diff --git a/src/tests/test_cases/test.py b/src/tests/test_cases/test.py
index 20b81fce..3d671e59 100644
--- a/src/tests/test_cases/test.py
+++ b/src/tests/test_cases/test.py
@@ -1,4 +1,3 @@
-# encoding: utf-8
 # No docstring, so we can test D100
 from functools import wraps
 import os
@@ -280,16 +279,6 @@ def exceptions_of_D301():
     """
 
 
-if sys.version_info[0] <= 2:
-    @expect('D302: Use u""" for Unicode docstrings')
-    def unicode_unmarked():
-        """Юникод."""
-
-    @expect('D302: Use u""" for Unicode docstrings')
-    def first_word_has_unicode_byte():
-        """あy."""
-
-
 @expect("D400: First line should end with a period (not 'y')")
 @expect("D415: First line should end with a period, question mark, "
         "or exclamation point (not 'y')")
diff --git a/src/tests/test_cases/unicode_literals.py b/src/tests/test_cases/unicode_literals.py
index 5f7dd700..f0aa466e 100644
--- a/src/tests/test_cases/unicode_literals.py
+++ b/src/tests/test_cases/unicode_literals.py
@@ -1,7 +1,5 @@
-# -*- coding: utf-8 -*-
 """A module."""
 
-from __future__ import unicode_literals
 from .expected import Expectation
 
 
diff --git a/src/tests/test_definitions.py b/src/tests/test_definitions.py
index 83109b5a..b2bd0081 100644
--- a/src/tests/test_definitions.py
+++ b/src/tests/test_definitions.py
@@ -26,7 +26,7 @@
 ])
 def test_complex_file(test_case):
     """Run domain-specific tests from test.py file."""
-    case_module = __import__('test_cases.{}'.format(test_case),
+    case_module = __import__(f'test_cases.{test_case}',
                              globals=globals(),
                              locals=locals(),
                              fromlist=['expectation'],
diff --git a/src/tests/test_integration.py b/src/tests/test_integration.py
index c5375c79..7de3b755 100644
--- a/src/tests/test_integration.py
+++ b/src/tests/test_integration.py
@@ -1,8 +1,5 @@
-# -*- coding: utf-8 -*-
-
 """Use tox or py.test to run the test-suite."""
 
-from __future__ import with_statement
 from collections import namedtuple
 
 import os
@@ -52,7 +49,7 @@ def write_config(self, prefix='', name='tox.ini', **kwargs):
             self.makedirs(base)
 
         with open(os.path.join(base, name), 'wt') as conf:
-            conf.write("[{}]\n".format(self.script_name))
+            conf.write(f"[{self.script_name}]\n")
             for k, v in kwargs.items():
                 conf.write("{} = {}\n".format(k.replace('_', '-'), v))
 
@@ -284,7 +281,7 @@ def test_sectionless_config_file(env):
         conf.write('[pdcstl]')
         config_path = conf.name
 
-    _, err, code = env.invoke('--config={}'.format(config_path))
+    _, err, code = env.invoke(f'--config={config_path}')
     assert code == 0
     assert 'Configuration file does not contain a pydocstyle section' in err
 
diff --git a/tox.ini b/tox.ini
index 7d85e7ed..e6d08656 100644
--- a/tox.ini
+++ b/tox.ini
@@ -4,7 +4,7 @@
 # install tox" and then run "tox" from this directory.
 
 [tox]
-envlist = {py35,py36,py37,py38,py39}-{tests,install},docs,install,py36-docs
+envlist = {py36,py37,py38,py39}-{tests,install},docs,install,py36-docs
 
 [testenv]
 download = true
@@ -42,10 +42,6 @@ commands = {[testenv:docs]commands}
 # There's no way to generate sub-sections in tox.
 # The following sections are all references to the `py37-install`.
 
-[testenv:py35-install]
-skip_install = {[testenv:install]skip_install}
-commands = {[testenv:install]commands}
-
 [testenv:py36-install]
 skip_install = {[testenv:install]skip_install}
 commands = {[testenv:install]commands}
@@ -58,6 +54,10 @@ commands = {[testenv:install]commands}
 skip_install = {[testenv:install]skip_install}
 commands = {[testenv:install]commands}
 
+[testenv:py39-install]
+skip_install = {[testenv:install]skip_install}
+commands = {[testenv:install]commands}
+
 [pytest]
 pep8ignore =
     test.py E701 E704