diff --git a/doc/language/packed_data.rdoc b/doc/language/packed_data.rdoc
index 088e6d86536db7..597db5139f87b2 100644
--- a/doc/language/packed_data.rdoc
+++ b/doc/language/packed_data.rdoc
@@ -457,15 +457,15 @@ for one byte in the input or output string.
     "foo ".unpack('A4')      # => ["foo"]
     "foo".unpack('A4')       # => ["foo"]
 
-    russian = "\u{442 435 441 442}" # => "тест"
-    russian.size         # => 4
-    russian.bytesize     # => 8
-    [russian].pack('A')  # => "\xD1"
-    [russian].pack('A*') # => "\xD1\x82\xD0\xB5\xD1\x81\xD1\x82"
-    russian.unpack('A')  # => ["\xD1"]
-    russian.unpack('A2') # => ["\xD1\x82"]
-    russian.unpack('A4') # => ["\xD1\x82\xD0\xB5"]
-    russian.unpack('A*') # => ["\xD1\x82\xD0\xB5\xD1\x81\xD1\x82"]
+    japanese = 'こんにちは'
+    japanese.size         # => 5
+    japanese.bytesize     # => 15
+    [japanese].pack('A')  # => "\xE3"
+    [japanese].pack('A*') # => "\xE3\x81\x93\xE3\x82\x93\xE3\x81\xAB\xE3\x81\xA1\xE3\x81\xAF"
+    japanese.unpack('A')  # => ["\xE3"]
+    japanese.unpack('A2') # => ["\xE3\x81"]
+    japanese.unpack('A4') # => ["\xE3\x81\x93\xE3"]
+    japanese.unpack('A*') # => ["\xE3\x81\x93\xE3\x82\x93\xE3\x81\xAB\xE3\x81\xA1\xE3\x81\xAF"]
 
 - <tt>'a'</tt> - Arbitrary binary string (null padded; count is width):
 
diff --git a/doc/string/aref.rdoc b/doc/string/aref.rdoc
index ee4c3d33d4e655..59c6ae97ace01e 100644
--- a/doc/string/aref.rdoc
+++ b/doc/string/aref.rdoc
@@ -8,7 +8,6 @@ returns the 1-character substring found in self at character offset index:
   'hello'[0]    # => "h"
   'hello'[4]    # => "o"
   'hello'[5]    # => nil
-  'Привет'[2]   # => "и"
   'こんにちは'[4] # => "は"
 
 With negative integer argument +index+ given,
@@ -92,7 +91,6 @@ returns the matching substring of +self+, if found:
   'hello'['ell']      # => "ell"
   'hello'['']         # => ""
   'hello'['nosuch']   # => nil
-  'Привет'['ив']      # => "ив"
   'こんにちは'['んにち'] # => "んにち"
 
 Related: see {Converting to New String}[rdoc-ref:String@Converting+to+New+String].
diff --git a/doc/string/aset.rdoc b/doc/string/aset.rdoc
index db9079ebfb8188..98c58b59cc43a1 100644
--- a/doc/string/aset.rdoc
+++ b/doc/string/aset.rdoc
@@ -170,10 +170,6 @@ With string argument +substring+ given:
   s['ll'] = 'foo'  # => "foo"
   s  # => "hefooo"
 
-  s = 'Привет'
-  s['ив'] = 'foo'  # => "foo"
-  s  # => "Прfooет"
-
   s = 'こんにちは'
   s['んにち'] = 'foo'  # => "foo"
   s  # => "こfooは"
diff --git a/doc/string/bytes.rdoc b/doc/string/bytes.rdoc
index 3815f13276fa11..6dde0a745d9b84 100644
--- a/doc/string/bytes.rdoc
+++ b/doc/string/bytes.rdoc
@@ -1,7 +1,6 @@
 Returns an array of the bytes in +self+:
 
   'hello'.bytes  # => [104, 101, 108, 108, 111]
-  'Привет'.bytes # => [208, 159, 209, 128, 208, 184, 208, 178, 208, 181, 209, 130]
   'こんにちは'.bytes
   # => [227, 129, 147, 227, 130, 147, 227, 129, 171, 227, 129, 161, 227, 129, 175]
 
diff --git a/doc/string/bytesize.rdoc b/doc/string/bytesize.rdoc
index cbb7f439fcb448..8d12a0d454fbac 100644
--- a/doc/string/bytesize.rdoc
+++ b/doc/string/bytesize.rdoc
@@ -5,9 +5,6 @@ Note that the byte count may be different from the character count (returned by
   s = 'foo'
   s.bytesize # => 3
   s.size     # => 3
-  s = 'Привет'
-  s.bytesize # => 12
-  s.size     # => 6
   s = 'こんにちは'
   s.bytesize # => 15
   s.size     # => 5
diff --git a/doc/string/capitalize.rdoc b/doc/string/capitalize.rdoc
index 9b26c0215342db..3a1a2dcb8b7c90 100644
--- a/doc/string/capitalize.rdoc
+++ b/doc/string/capitalize.rdoc
@@ -10,8 +10,6 @@ Examples:
   'HELLO'.capitalize  # => "Hello"
   'straße'.capitalize # => "Straße"  # Lowercase 'ß' not changed.
   'STRAẞE'.capitalize # => "Straße"  # Uppercase 'ẞ' downcased to 'ß'.
-  'привет'.capitalize # => "Привет"
-  'ПРИВЕТ'.capitalize # => "Привет"
 
 Some characters (and some character sets) do not have upcase and downcase versions;
 see {Case Mapping}[rdoc-ref:case_mapping.rdoc]:
diff --git a/doc/string/center.rdoc b/doc/string/center.rdoc
index 3116d211174286..b86c8b59169933 100644
--- a/doc/string/center.rdoc
+++ b/doc/string/center.rdoc
@@ -9,7 +9,6 @@ centered and padded on one or both ends with +pad_string+:
   'hello'.center(20, '-|')      # => "-|-|-|-hello-|-|-|-|" # Some padding repeated.
   'hello'.center(10, 'abcdefg') # => "abhelloabc"           # Some padding not used.
   '  hello  '.center(13)        # => "    hello    "
-  'Привет'.center(10)           # => "  Привет  "
   'こんにちは'.center(10)         # => "  こんにちは   "      # Multi-byte characters.
 
 If +size+ is less than or equal to the size of +self+, returns an unpadded copy of +self+:
diff --git a/doc/string/chars.rdoc b/doc/string/chars.rdoc
index 97ea07331f4c46..d4d15bf2ad541d 100644
--- a/doc/string/chars.rdoc
+++ b/doc/string/chars.rdoc
@@ -1,7 +1,6 @@
 Returns an array of the characters in +self+:
 
   'hello'.chars     # => ["h", "e", "l", "l", "o"]
-  'Привет'.chars    # => ["П", "р", "и", "в", "е", "т"]
   'こんにちは'.chars # => ["こ", "ん", "に", "ち", "は"]
   ''.chars          # => []
 
diff --git a/doc/string/chomp.rdoc b/doc/string/chomp.rdoc
index 6ec7664f6b6832..4efff5c2917e9c 100644
--- a/doc/string/chomp.rdoc
+++ b/doc/string/chomp.rdoc
@@ -9,7 +9,6 @@ if they are <tt>"\r"</tt>, <tt>"\n"</tt>, or <tt>"\r\n"</tt>
   "abc\n".chomp         # => "abc"
   "abc\r\n".chomp       # => "abc"
   "abc\n\r".chomp       # => "abc\n"
-  "тест\r\n".chomp      # => "тест"
   "こんにちは\r\n".chomp  # => "こんにちは"
 
 When +line_sep+ is <tt>''</tt> (an empty string),
diff --git a/doc/string/chop.rdoc b/doc/string/chop.rdoc
index 2c48e911292eff..d818ba467ac062 100644
--- a/doc/string/chop.rdoc
+++ b/doc/string/chop.rdoc
@@ -3,13 +3,11 @@ Returns a new string copied from +self+, with trailing characters possibly remov
 Removes <tt>"\r\n"</tt> if those are the last two characters.
 
   "abc\r\n".chop      # => "abc"
-  "тест\r\n".chop     # => "тест"
   "こんにちは\r\n".chop # => "こんにちは"
 
 Otherwise removes the last character if it exists.
 
   'abcd'.chop     # => "abc"
-  'тест'.chop     # => "тес"
   'こんにちは'.chop # => "こんにち"
   ''.chop         # => ""
 
diff --git a/doc/string/chr.rdoc b/doc/string/chr.rdoc
index 1ada3854cbeb27..153d5d71c325ba 100644
--- a/doc/string/chr.rdoc
+++ b/doc/string/chr.rdoc
@@ -1,7 +1,6 @@
 Returns a string containing the first character of +self+:
 
   'hello'.chr     # => "h"
-  'тест'.chr      # => "т"
   'こんにちは'.chr # => "こ"
   ''.chr          # => ""
 
diff --git a/doc/string/codepoints.rdoc b/doc/string/codepoints.rdoc
index d9586d2e0bc2a5..22cb22c8890df1 100644
--- a/doc/string/codepoints.rdoc
+++ b/doc/string/codepoints.rdoc
@@ -2,7 +2,6 @@ Returns an array of the codepoints in +self+;
 each codepoint is the integer value for a character:
 
   'hello'.codepoints     # => [104, 101, 108, 108, 111]
-  'тест'.codepoints      # => [1090, 1077, 1089, 1090]
   'こんにちは'.codepoints # => [12371, 12435, 12395, 12385, 12399]
   ''.codepoints          # => []
 
diff --git a/doc/string/concat.rdoc b/doc/string/concat.rdoc
index 2ba0c714af57d3..92ba664b8cb825 100644
--- a/doc/string/concat.rdoc
+++ b/doc/string/concat.rdoc
@@ -6,7 +6,6 @@ For each given object +object+ that is an integer,
 the value is considered a codepoint and converted to a character before concatenation:
 
   'foo'.concat(32, 'bar', 32, 'baz') # => "foo bar baz" # Embeds spaces.
-  'те'.concat(1089, 1090)            # => "тест"
   'こん'.concat(12395, 12385, 12399)  # => "こんにちは"
 
 Related: see {Converting to New String}[rdoc-ref:String@Converting+to+New+String].
diff --git a/doc/string/count.rdoc b/doc/string/count.rdoc
index 092c672d7d113b..7a3b9f1e211ebf 100644
--- a/doc/string/count.rdoc
+++ b/doc/string/count.rdoc
@@ -9,10 +9,6 @@ returns the count of instances of that character:
   s.count('x') # => 0
   s.count('')  # => 0
 
-  s = 'тест'
-  s.count('т')  # => 2
-  s.count('е')  # => 1
-
   s = 'よろしくお願いします'
   s.count('よ')  # => 1
   s.count('し')  # => 2
diff --git a/doc/string/delete.rdoc b/doc/string/delete.rdoc
index e8ff4c0ae400af..1827f177e6cd87 100644
--- a/doc/string/delete.rdoc
+++ b/doc/string/delete.rdoc
@@ -10,10 +10,6 @@ removes all instances of that character:
   s.delete('x') # => "abracadabra"
   s.delete('')  # => "abracadabra"
 
-  s = 'тест'
-  s.delete('т') # => "ес"
-  s.delete('е') # => "тст"
-
   s = 'よろしくお願いします'
   s.delete('よ') # => "ろしくお願いします"
   s.delete('し') # => "よろくお願います"
diff --git a/doc/string/delete_prefix.rdoc b/doc/string/delete_prefix.rdoc
index 1135f3d19d26ed..6255e300e350d4 100644
--- a/doc/string/delete_prefix.rdoc
+++ b/doc/string/delete_prefix.rdoc
@@ -4,7 +4,6 @@ Returns a copy of +self+ with leading substring +prefix+ removed:
   'oof'.delete_prefix('oo')         # => "f"
   'oof'.delete_prefix('oof')        # => ""
   'oof'.delete_prefix('x')          # => "oof"
-  'тест'.delete_prefix('те')        # => "ст"
   'こんにちは'.delete_prefix('こん')  # => "にちは"
 
 Related: see {Converting to New String}[rdoc-ref:String@Converting+to+New+String].
diff --git a/doc/string/delete_suffix.rdoc b/doc/string/delete_suffix.rdoc
index 2fb70ce012aabc..a4d9a80f85fb4d 100644
--- a/doc/string/delete_suffix.rdoc
+++ b/doc/string/delete_suffix.rdoc
@@ -5,7 +5,6 @@ Returns a copy of +self+ with trailing substring <tt>suffix</tt> removed:
   'foo'.delete_suffix('foo')         # => ""
   'foo'.delete_suffix('f')           # => "foo"
   'foo'.delete_suffix('x')           # => "foo"
-  'тест'.delete_suffix('ст')         # => "те"
   'こんにちは'.delete_suffix('ちは')  # => "こんに"
 
 Related: see {Converting to New String}[rdoc-ref:String@Converting+to+New+String].
diff --git a/doc/string/dump.rdoc b/doc/string/dump.rdoc
index 2ab9521540dcda..add3c356623b15 100644
--- a/doc/string/dump.rdoc
+++ b/doc/string/dump.rdoc
@@ -69,10 +69,6 @@ and so contains both outer double-quotes and escaped inner double-quotes:
 If +self+ is encoded in UTF-8 and contains Unicode characters,
 each Unicode character is dumped as a Unicode escape sequence:
 
-  String:    тест
-  Dumped:    "\u0442\u0435\u0441\u0442"
-  Undumped:  тест
-
   String:    こんにちは
   Dumped:    "\u3053\u3093\u306B\u3061\u306F"
   Undumped:  こんにちは
@@ -88,10 +84,6 @@ where <tt><encoding></tt> is <tt>self.encoding.name</tt>:
   Dumped:    "\xFE\xFF\x00h\x00e\x00l\x00l\x00o".dup.force_encoding("UTF-16")
   Undumped:  hello
 
-  String:    тест
-  Dumped:    "\xFE\xFF\x04B\x045\x04A\x04B".dup.force_encoding("UTF-16")
-  Undumped:  тест
-
   String:    こんにちは
   Dumped:    "\xFE\xFF0S0\x930k0a0o".dup.force_encoding("UTF-16")
   Undumped:  こんにちは
diff --git a/doc/string/each_byte.rdoc b/doc/string/each_byte.rdoc
index 1f1069863b264b..642d71e84b5408 100644
--- a/doc/string/each_byte.rdoc
+++ b/doc/string/each_byte.rdoc
@@ -5,9 +5,6 @@ returns +self+:
   'hello'.each_byte {|byte| a.push(byte) }     # Five 1-byte characters.
   a # => [104, 101, 108, 108, 111]
   a = []
-  'тест'.each_byte {|byte| a.push(byte) }      # Four 2-byte characters.
-  a # => [209, 130, 208, 181, 209, 129, 209, 130]
-  a = []
   'こんにちは'.each_byte {|byte| a.push(byte) }  # Five 3-byte characters.
   a # => [227, 129, 147, 227, 130, 147, 227, 129, 171, 227, 129, 161, 227, 129, 175]
 
diff --git a/doc/string/each_char.rdoc b/doc/string/each_char.rdoc
index 5aa85b28ad9dd1..2dd56711d3b076 100644
--- a/doc/string/each_char.rdoc
+++ b/doc/string/each_char.rdoc
@@ -7,11 +7,6 @@ returns +self+:
   end
   a # => ["h", "e", "l", "l", "o"]
   a = []
-  'тест'.each_char do |char|
-    a.push(char)
-  end
-  a # => ["т", "е", "с", "т"]
-  a = []
   'こんにちは'.each_char do |char|
     a.push(char)
   end
diff --git a/doc/string/each_codepoint.rdoc b/doc/string/each_codepoint.rdoc
index 0e687082d3ed4c..8e4e7545e62a76 100644
--- a/doc/string/each_codepoint.rdoc
+++ b/doc/string/each_codepoint.rdoc
@@ -8,11 +8,6 @@ returns +self+:
   end
   a # => [104, 101, 108, 108, 111]
   a = []
-  'тест'.each_codepoint do |codepoint|
-    a.push(codepoint)
-  end
-  a # => [1090, 1077, 1089, 1090]
-  a = []
   'こんにちは'.each_codepoint do |codepoint|
     a.push(codepoint)
   end
diff --git a/doc/string/each_grapheme_cluster.rdoc b/doc/string/each_grapheme_cluster.rdoc
index 8bc6f78aaa374d..384cd6967d5db3 100644
--- a/doc/string/each_grapheme_cluster.rdoc
+++ b/doc/string/each_grapheme_cluster.rdoc
@@ -8,12 +8,6 @@ returns +self+:
   end
   a  # => ["h", "e", "l", "l", "o"]
 
-  a = []
-  'тест'.each_grapheme_cluster do |grapheme_cluster|
-    a.push(grapheme_cluster)
-  end
-  a # => ["т", "е", "с", "т"]
-
   a = []
   'こんにちは'.each_grapheme_cluster do |grapheme_cluster|
     a.push(grapheme_cluster)
diff --git a/doc/string/end_with_p.rdoc b/doc/string/end_with_p.rdoc
index fcd92421225ca8..9a95d74fde5ba0 100644
--- a/doc/string/end_with_p.rdoc
+++ b/doc/string/end_with_p.rdoc
@@ -4,7 +4,6 @@ Returns whether +self+ ends with any of the given +strings+:
   'foo'.end_with?('bar', 'oo')  # => true
   'foo'.end_with?('bar', 'baz') # => false
   'foo'.end_with?('')           # => true
-  'тест'.end_with?('т')         # => true
   'こんにちは'.end_with?('は')   # => true
 
 Related: see {Querying}[rdoc-ref:String@Querying].
diff --git a/doc/string/getbyte.rdoc b/doc/string/getbyte.rdoc
index ba1c06fd27cb67..1d0ed2a5a488ad 100644
--- a/doc/string/getbyte.rdoc
+++ b/doc/string/getbyte.rdoc
@@ -16,9 +16,6 @@ Returns +nil+ if +index+ is out of range:
 
 More examples:
 
-  s = 'тест'
-  s.bytes      # => [209, 130, 208, 181, 209, 129, 209, 130]
-  s.getbyte(2) # => 208
   s = 'こんにちは'
   s.bytes      # => [227, 129, 147, 227, 130, 147, 227, 129, 171, 227, 129, 161, 227, 129, 175]
   s.getbyte(2) # => 147
diff --git a/doc/string/index.rdoc b/doc/string/index.rdoc
index 6045fac0f6fb5a..c3cff24dac5a48 100644
--- a/doc/string/index.rdoc
+++ b/doc/string/index.rdoc
@@ -8,7 +8,6 @@ returns the index of the first matching substring in +self+:
   'foo'.index('o')         # => 1
   'foo'.index('oo')        # => 1
   'foo'.index('ooo')       # => nil
-  'тест'.index('с')        # => 2  # Characters, not bytes.
   'こんにちは'.index('ち')  # => 3
 
 When +pattern+ is a Regexp, returns the index of the first match in +self+:
@@ -24,9 +23,6 @@ the returned index is relative to the beginning of +self+:
   'bar'.index('r', 2)        # => 2
   'bar'.index('r', 3)        # => nil
   'bar'.index(/[r-z]/, 0)    # => 2
-  'тест'.index('с', 1)       # => 2
-  'тест'.index('с', 2)       # => 2
-  'тест'.index('с', 3)       # => nil  # Offset in characters, not bytes.
   'こんにちは'.index('ち', 2) # => 3
 
 With negative integer argument +offset+, selects the search position by counting backward
diff --git a/doc/string/insert.rdoc b/doc/string/insert.rdoc
index d8252d5ec5fd81..73205f20693cc7 100644
--- a/doc/string/insert.rdoc
+++ b/doc/string/insert.rdoc
@@ -5,7 +5,6 @@ If the given +index+ is non-negative, inserts +other_string+ at offset +index+:
   'foo'.insert(0, 'bar')       # => "barfoo"
   'foo'.insert(1, 'bar')       # => "fbaroo"
   'foo'.insert(3, 'bar')       # => "foobar"
-  'тест'.insert(2, 'bar')      # => "теbarст"  # Characters, not bytes.
   'こんにちは'.insert(2, 'bar') # => "こんbarにちは"
 
 If the +index+ is negative, counts backward from the end of +self+
diff --git a/doc/string/inspect.rdoc b/doc/string/inspect.rdoc
index 828ecf966dd26f..907828c2afc22c 100644
--- a/doc/string/inspect.rdoc
+++ b/doc/string/inspect.rdoc
@@ -6,7 +6,6 @@ Most printable characters are rendered simply as themselves:
   '012'.inspect        # => "\"012\""
   ''.inspect           # => "\"\""
   "\u000012".inspect   # => "\"\\u000012\""
-  'тест'.inspect       # => "\"тест\""
   'こんにちは'.inspect  # => "\"こんにちは\""
 
 But printable characters double-quote (<tt>'"'</tt>) and backslash and (<tt>'\\'</tt>) are escaped:
diff --git a/doc/string/intern.rdoc b/doc/string/intern.rdoc
index 1336e4688f7a2e..eded6ac3d727c9 100644
--- a/doc/string/intern.rdoc
+++ b/doc/string/intern.rdoc
@@ -2,7 +2,6 @@ Returns the Symbol object derived from +self+,
 creating it if it did not already exist:
 
   'foo'.intern       # => :foo
-  'тест'.intern      # => :тест
   'こんにちは'.intern # => :こんにちは
 
 Related: see {Converting to Non-String}[rdoc-ref:String@Converting+to+Non--5CString].
diff --git a/doc/string/length.rdoc b/doc/string/length.rdoc
index 5b302380b59fdb..eb68edb10c449f 100644
--- a/doc/string/length.rdoc
+++ b/doc/string/length.rdoc
@@ -1,13 +1,11 @@
 Returns the count of characters (not bytes) in +self+:
 
   'foo'.length        # => 3
-  'тест'.length       # => 4
   'こんにちは'.length  # => 5
 
 Contrast with String#bytesize:
 
   'foo'.bytesize        # => 3
-  'тест'.bytesize       # => 8
   'こんにちは'.bytesize  # => 15
 
 Related: see {Querying}[rdoc-ref:String@Querying].
diff --git a/doc/string/ljust.rdoc b/doc/string/ljust.rdoc
index f37c0b3151176d..a8ca62ee764c6d 100644
--- a/doc/string/ljust.rdoc
+++ b/doc/string/ljust.rdoc
@@ -3,7 +3,6 @@ Returns a copy of +self+, left-justified and, if necessary, right-padded with th
   'hello'.ljust(10)       # => "hello     "
   '  hello'.ljust(10)     # => "  hello   "
   'hello'.ljust(10, 'ab') # => "helloababa"
-  'тест'.ljust(10)        # => "тест      "
   'こんにちは'.ljust(10)   # => "こんにちは     "
 
 If <tt>width <= self.length</tt>, returns a copy of +self+:
diff --git a/doc/string/ord.rdoc b/doc/string/ord.rdoc
index a5ddbb4e2fb82a..87b469db0205ce 100644
--- a/doc/string/ord.rdoc
+++ b/doc/string/ord.rdoc
@@ -2,7 +2,6 @@ Returns the integer ordinal of the first character of +self+:
 
   'h'.ord         # => 104
   'hello'.ord     # => 104
-  'тест'.ord      # => 1090
   'こんにちは'.ord  # => 12371
 
 Related: see {Converting to Non-String}[rdoc-ref:String@Converting+to+Non--5CString].
diff --git a/doc/string/partition.rdoc b/doc/string/partition.rdoc
index d822f8ec0e0738..614ad029d49885 100644
--- a/doc/string/partition.rdoc
+++ b/doc/string/partition.rdoc
@@ -38,7 +38,6 @@ then performs the equivalent of <tt>self.index(pattern)</tt>
   'hello'.partition('o')     # => ["hell", "o", ""]
   'hello'.partition('')      # => ["", "", "hello"]
   'hello'.partition('x')     # => ["hello", "", ""]
-  'тест'.partition('т')      # => ["", "т", "ест"]
   'こんにちは'.partition('に') # => ["こん", "に", "ちは"]
 
 Related: see {Converting to Non-String}[rdoc-ref:String@Converting+to+Non--5CString].
diff --git a/doc/string/rindex.rdoc b/doc/string/rindex.rdoc
index 8a1cc0106f59fb..2b81c3716d2986 100644
--- a/doc/string/rindex.rdoc
+++ b/doc/string/rindex.rdoc
@@ -7,7 +7,6 @@ When +pattern+ is a string, returns the index of the last matching substring in
   'foo'.rindex('o')       # => 2
   'foo'.rindex('oo'       # => 1
   'foo'.rindex('ooo')     # => nil
-  'тест'.rindex('т')      # => 3
   'こんにちは'.rindex('ち') # => 3
 
 When +pattern+ is a Regexp, returns the index of the last match in self:
diff --git a/doc/string/rjust.rdoc b/doc/string/rjust.rdoc
index 864cfcce7a0ec0..acd3f198d46fe0 100644
--- a/doc/string/rjust.rdoc
+++ b/doc/string/rjust.rdoc
@@ -7,7 +7,6 @@ right justified and padded on the left with +pad_string+:
   'hello'.rjust(10)       # => "     hello"
   'hello  '.rjust(10)     # => "   hello  "
   'hello'.rjust(10, 'ab') # => "ababahello"
-  'тест'.rjust(10)        # => "      тест"
   'こんにちは'.rjust(10)    # => "     こんにちは"
 
 If <tt>width <= self.size</tt>, returns a copy of +self+:
diff --git a/doc/string/rpartition.rdoc b/doc/string/rpartition.rdoc
index 6a17b5e944bffc..eed03949a56e52 100644
--- a/doc/string/rpartition.rdoc
+++ b/doc/string/rpartition.rdoc
@@ -31,7 +31,6 @@ If +pattern+ is a Regexp, searches for the last matching substring
   'hello'.rpartition(/o/)     # => ["hell", "o", ""]
   'hello'.rpartition(//)      # => ["hello", "", ""]
   'hello'.rpartition(/x/)     # => ["", "", "hello"]
-  'тест'.rpartition(/т/)      # => ["тес", "т", ""]
   'こんにちは'.rpartition(/に/) # => ["こん", "に", "ちは"]
 
 If +pattern+ is not a Regexp, converts it to a string (if it is not already one),
@@ -43,7 +42,6 @@ then searches for the last matching substring
   'hello'.rpartition('h')     # => ["", "h", "ello"]
   'hello'.rpartition('o')     # => ["hell", "o", ""]
   'hello'.rpartition('')      # => ["hello", "", ""]
-  'тест'.rpartition('т')      # => ["тес", "т", ""]
   'こんにちは'.rpartition('に') # => ["こん", "に", "ちは"]
 
 Related: see {Converting to Non-String}[rdoc-ref:String@Converting+to+Non--5CString].
diff --git a/doc/string/scan.rdoc b/doc/string/scan.rdoc
index cbede5280f5c49..04a2b02ff4ec1b 100644
--- a/doc/string/scan.rdoc
+++ b/doc/string/scan.rdoc
@@ -16,7 +16,6 @@ With no block given, returns an array of the results:
   'cruel world'.scan(/.../)      # => ["cru", "el ", "wor"]
   'cruel world'.scan(/(...)/)    # => [["cru"], ["el "], ["wor"]]
   'cruel world'.scan(/(..)(..)/) # => [["cr", "ue"], ["l ", "wo"]]
-  'тест'.scan(/../)              # => ["те", "ст"]
   'こんにちは'.scan(/../)         # => ["こん", "にち"]
   'abracadabra'.scan('ab')       # => ["ab", "ab"]
   'abracadabra'.scan('nosuch')   # => []
diff --git a/doc/string/split.rdoc b/doc/string/split.rdoc
index 9e61bc5bab3751..1aee1de0a4cca7 100644
--- a/doc/string/split.rdoc
+++ b/doc/string/split.rdoc
@@ -23,7 +23,6 @@ splits at every character:
 
   'abracadabra'.split('') # => ["a", "b", "r", "a", "c", "a", "d", "a", "b", "r", "a"]
   ''.split('')            # => []
-  'тест'.split('')        # => ["т", "е", "с", "т"]
   'こんにちは'.split('')   # => ["こ", "ん", "に", "ち", "は"]
 
 When +field_sep+ is a non-empty string and different from <tt>' '</tt> (a single space),
@@ -32,7 +31,6 @@ uses that string as the separator:
   'abracadabra'.split('a')  # => ["", "br", "c", "d", "br"]
   'abracadabra'.split('ab') # => ["", "racad", "ra"]
   ''.split('a')             # => []
-  'тест'.split('т')         # => ["", "ес"]
   'こんにちは'.split('に')    # => ["こん", "ちは"]
 
 When +field_sep+ is a Regexp,
diff --git a/doc/string/start_with_p.rdoc b/doc/string/start_with_p.rdoc
index 298a5572769ea8..f78edc7fa3b63f 100644
--- a/doc/string/start_with_p.rdoc
+++ b/doc/string/start_with_p.rdoc
@@ -11,7 +11,6 @@ Returns +true+ if any pattern matches the beginning, +false+ otherwise:
   'hello'.start_with?(/H/i)                 # => true
   'hello'.start_with?('heaven', 'hell')     # => true
   'hello'.start_with?('heaven', 'paradise') # => false
-  'тест'.start_with?('т')                   # => true
   'こんにちは'.start_with?('こ')              # => true
 
 Related: see {Querying}[rdoc-ref:String@Querying].
diff --git a/doc/string/succ.rdoc b/doc/string/succ.rdoc
index 3653112b837e3c..1b4b936a8e8351 100644
--- a/doc/string/succ.rdoc
+++ b/doc/string/succ.rdoc
@@ -7,7 +7,6 @@ or, if no alphanumerics, the rightmost character:
   'THX1138'.succ   # => "THX1139"
   '<<koala>>'.succ # => "<<koalb>>"
   '***'.succ       # => '**+'
-  'тест'.succ      # => "тесу"
   'こんにちは'.succ  # => "こんにちば"
 
 The successor to a digit is another digit, "carrying" to the next-left
diff --git a/doc/string/sum.rdoc b/doc/string/sum.rdoc
index 125611411e34ab..22045e5f4ddc5a 100644
--- a/doc/string/sum.rdoc
+++ b/doc/string/sum.rdoc
@@ -5,7 +5,6 @@ modulo <tt>2**n - 1</tt>:
   'hello'.sum     # => 532
   'hello'.sum(4)  # => 4
   'hello'.sum(64) # => 532
-  'тест'.sum      # => 1405
   'こんにちは'.sum  # => 2582
 
 This is not a particularly strong checksum.
diff --git a/doc/string/swapcase.rdoc b/doc/string/swapcase.rdoc
index 916e711b7ec7b2..4353c8528a26b4 100644
--- a/doc/string/swapcase.rdoc
+++ b/doc/string/swapcase.rdoc
@@ -7,7 +7,6 @@ Examples:
 
   'Hello'.swapcase        # => "hELLO"
   'Straße'.swapcase       # => "sTRASSE"
-  'Привет'.swapcase       # => "пРИВЕТ"
   'RubyGems.org'.swapcase # => "rUBYgEMS.ORG"
 
 The sizes of +self+ and the upcased result may differ: