Index: Doc/library/urllib.rst
===================================================================
--- Doc/library/urllib.rst	(revision 78945)
+++ Doc/library/urllib.rst	(working copy)
@@ -225,8 +225,19 @@
 
    Replace ``%xx`` escapes by their single-character equivalent.
 
+   *string* may be either a :class:`str` or a :class:`unicode`.
+
+   If it is a :class:`unicode`, the result is also a :class:`unicode`.
+   Percent-escaped octets are decoded as Latin-1. (For example, the string
+   ``u'%FC'`` describes the Unicode character ``u'\00fc'``, rather than the
+   byte ``'\xfc'``.) To interpret the escaped characters with another
+   encoding, *string* should first be encoded as a :class:`str`, unquoted, and
+   then decoded with the desired encoding.
+
+
    Example: ``unquote('/%7Econnolly/')`` yields ``'/~connolly/'``.
 
+   Example: ``unquote(u'/El%20Ni%F1o/')`` yields ``u'/El Niño/'``.
 
 .. function:: unquote_plus(string)
 
Index: Lib/test/test_urllib.py
===================================================================
--- Lib/test/test_urllib.py	(revision 78945)
+++ Lib/test/test_urllib.py	(working copy)
@@ -463,9 +463,35 @@
         self.assertEqual(expect, result,
                          "using unquote_plus(): %s != %s" % (expect, result))
 
+    def test_unquote_nonascii_bytes(self):
+        # Test on escaped non-ASCII bytes
+        given = '%A2%D8ab%FF'
+        expect = b'\xa2\xd8ab\xff'
+        result = urllib.unquote(given)
+        self.assertEqual(expect, result, "using unquote(): %r != %r"
+                         % (expect, result))
+        # Test on unescaped non-ASCII bytes
+        # (Technically an invalid URI; expect those bytes to be preserved)
+        given = b'%A2\xd8ab%FF'
+        expect = b'\xa2\xd8ab\xff'
+        result = urllib.unquote(given)
+        self.assertEqual(expect, result, "using unquote(): %r != %r"
+                         % (expect, result))
+
     def test_unquote_with_unicode(self):
-        r = urllib.unquote(u'br%C3%BCckner_sapporo_20050930.doc')
-        self.assertEqual(r, u'br\xc3\xbcckner_sapporo_20050930.doc')
+        # Percent-escaped characters in unicode strings are decoded with
+        # Latin-1. (This is not ideal, but necessary for historical reasons --
+        # see issue #8136).
+        r = urllib.unquote(u'br%FCckner_sapporo_20050930.doc')
+        self.assertEqual(r, u'br\u00fcckner_sapporo_20050930.doc')
+        # Test on a string with unescaped non-ASCII characters
+        # (Technically an invalid URI; expect those characters to be UTF-8
+        # encoded).
+        given = u'\u6f22%FC%EA'
+        result = urllib.unquote(given)
+        expect = u'\u6f22\xfc\xea'
+        self.assertEqual(expect, result,
+                         "using unquote(): %r != %r" % (expect, result))
 
 class urlencode_Tests(unittest.TestCase):
     """Tests for urlencode()"""