diff --git a/.gitignore b/.gitignore
index 69298645..a8e9e8cb 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,7 +1,7 @@
 deb_dist
 build
 dist
-.gitignore
+#.gitignore
 *~
 *.aux
 *.sbd
diff --git a/NEWS.md b/NEWS.md
index 4e374f6c..06eb7aab 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -9,6 +9,7 @@
     * Fix the import when the content folder is zipped [#235](https://github.com/patacrep/patacrep/pull/235)
   * PDF generation
     * The bookmarks correctly use the unicode encoding [#225](https://github.com/patacrep/patacrep/pull/225)
+    * The first letters of the index are "unidecoded" [#231](https://github.com/patacrep/patacrep/pull/231)
 * Enhancements
   * Error management
     * The 'error' option is considered for contentlist errors (incorrect syntax for instance) [#226](https://github.com/patacrep/patacrep/pull/226)
diff --git a/patacrep/build.py b/patacrep/build.py
index a66619d7..15a4ca78 100644
--- a/patacrep/build.py
+++ b/patacrep/build.py
@@ -307,8 +307,8 @@ class SongbookBuilder:
             raise errors.LatexCompilationError(self.basename)
 
     def build_sbx(self):
-        """Make index"""
-        LOGGER.info("Building indexes…")
+        """Make .sbx indexes from .sxd files"""
+        LOGGER.info("Building .sbx indexes…")
         sxd_files = glob.glob("%s_*.sxd" % self.basename)
         for sxd_file in sxd_files:
             LOGGER.debug("Processing " + sxd_file)
diff --git a/patacrep/content/sort.py b/patacrep/content/sort.py
index cb10d157..e4bde299 100755
--- a/patacrep/content/sort.py
+++ b/patacrep/content/sort.py
@@ -5,27 +5,17 @@ to a songbook.
 """
 
 import logging
-import unidecode
 
 from patacrep import files
 from patacrep.content import ContentError
 from patacrep.content import process_content, validate_parser_argument
 from patacrep.content.song import OnlySongsError
+from patacrep.utils import normalize_string
 
 LOGGER = logging.getLogger(__name__)
 
 DEFAULT_SORT = ['by', 'album', 'title']
 
-def normalize_string(string):
-    """Return a normalized string.
-
-    Normalized means:
-    - no surrounding spaces;
-    - lower case;
-    - passed through unidecode.unidecode().
-    """
-    return unidecode.unidecode(string.lower().strip())
-
 def normalize_field(field):
     """Return a normalized field, it being a string or a list of strings."""
     if isinstance(field, str):
diff --git a/patacrep/index.py b/patacrep/index.py
index e520e713..75d55107 100644
--- a/patacrep/index.py
+++ b/patacrep/index.py
@@ -7,11 +7,11 @@ from a file generated by the latex compilation of the songbook (.sxd).
 
 import locale
 import re
-import unidecode
 
 from patacrep import authors
 from patacrep import encoding
 from patacrep.latex import tex2plain
+from patacrep.utils import normalize_string
 
 EOL = "\n"
 
@@ -67,7 +67,7 @@ class Index:
     def get_first_letter(key):
         """Return the uppercase first letter of key."""
         try:
-            letter = FIRST_LETTER_PATTERN.match(key).group(1)
+            letter = FIRST_LETTER_PATTERN.match(normalize_string(key)).group(1)
         except AttributeError:
             # classify as number all the non letter characters
             letter = "0"
@@ -108,7 +108,7 @@ class Index:
         if key not in self.data[first]:
             self.data[first][key] = {
                 'sortingkey': [
-                    unidecode.unidecode(tex2plain(item)).lower()
+                    normalize_string(tex2plain(item))
                     for item in key
                     ],
                 'entries': [],
diff --git a/patacrep/utils.py b/patacrep/utils.py
index 5051a592..1d139f6a 100644
--- a/patacrep/utils.py
+++ b/patacrep/utils.py
@@ -1,6 +1,7 @@
 """Some utility functions"""
 
 from collections import UserDict
+import unidecode
 
 from patacrep import errors, Rx
 
@@ -92,3 +93,13 @@ def validate_yaml_schema(data, schema):
         schema.validate(data)
     except Rx.SchemaMismatch as exception:
         raise errors.SchemaError(rx_exception=exception)
+
+def normalize_string(string):
+    """Return a normalized string.
+
+    Normalized means:
+    - no surrounding spaces;
+    - lower case;
+    - passed through unidecode.unidecode().
+    """
+    return unidecode.unidecode(string.lower().strip())
diff --git a/setup.py b/setup.py
index aacfe910..aedd2009 100755
--- a/setup.py
+++ b/setup.py
@@ -7,6 +7,7 @@ $ python setup.py install
 from patacrep import __version__
 
 from setuptools import setup, find_packages
+import os
 import sys
 
 setup_kwargs = {
@@ -14,10 +15,28 @@ setup_kwargs = {
     }
 
 if sys.platform[0:3] == 'win':
-    from patacrep import __DATADIR__, files
+    from patacrep import __DATADIR__
+
+    def recursive_find(root_directory):
+        """Recursively find files from a root_directory.
+
+        Return a list of files matching those conditions.
+
+        Arguments:
+        - `root_directory`: root directory of the search.
+        """
+        if not os.path.isdir(root_directory):
+            return
+
+        olddir = os.getcwd()
+        os.chdir(root_directory)
+        for root, __ignored, filenames in os.walk(os.curdir):
+            for filename in filenames:
+                yield os.path.join(root, filename)
+        os.chdir(olddir)
 
     # List the data files
-    data_files = files.recursive_find(__DATADIR__)
+    data_files = recursive_find(__DATADIR__)
     data_files = ["data/" + d for d in data_files]
     setup_kwargs['package_data'] = {'patacrep': data_files}
 else:
diff --git a/test/test_content/test_content.py b/test/test_content/test_content.py
index 5edb9f96..1ca8c67d 100644
--- a/test/test_content/test_content.py
+++ b/test/test_content/test_content.py
@@ -42,7 +42,7 @@ class FileTest(unittest.TestCase, metaclass=dynamic.DynamicTest):
 
     @classmethod
     def _create_content_test(cls, base):
-        """Return a function that `base.source` produces the correct file list"""
+        """Return a function that tests that `base.source` produces the correct file list"""
 
         def test_content(self):
             """Test that `base.source` produces the correct file list"""
diff --git a/test/test_index/.gitignore b/test/test_index/.gitignore
new file mode 100644
index 00000000..371a68d1
--- /dev/null
+++ b/test/test_index/.gitignore
@@ -0,0 +1,2 @@
+!*.sxd
+!*.sbx
diff --git a/test/test_index/__init__.py b/test/test_index/__init__.py
new file mode 100644
index 00000000..e69de29b
diff --git a/test/test_index/idx_auth.sbx b/test/test_index/idx_auth.sbx
new file mode 100644
index 00000000..1063af69
--- /dev/null
+++ b/test/test_index/idx_auth.sbx
@@ -0,0 +1,26 @@
+\begin{idxblock}{A}
+  \idxentry{
+                \indexauthor{}{Aba}
+            }{
+                \hyperlink{song1-4.2}{4}
+            }  \idxentry{
+                \indexauthor{}{Äbc}
+            }{
+                \hyperlink{song1-2.2}{2}
+            }  \idxentry{
+                \indexauthor{}{Abd}
+            }{
+                \hyperlink{song1-3.2}{3}
+            }
+\end{idxblock}
+\begin{idxblock}{J}
+  \idxentry{
+                \indexauthor{}{Jack}
+            }{
+                \hyperlink{song1-1.2}{1}
+            }  \idxentry{
+                \indexauthor{}{Johns}
+            }{
+                \hyperlink{song1-1.2}{1}
+            }
+\end{idxblock}
diff --git a/test/test_index/idx_auth.sxd b/test/test_index/idx_auth.sxd
new file mode 100644
index 00000000..5d2f091b
--- /dev/null
+++ b/test/test_index/idx_auth.sxd
@@ -0,0 +1,19 @@
+AUTHOR INDEX DATA FILE
+%ignore unknown
+%after by
+%sep and
+Jack and Johns
+1
+song1-1.2
+Äbc
+2
+song1-2.2
+Abd
+3
+song1-3.2
+Aba
+4
+song1-4.2
+unknown
+5
+song1-5.2
diff --git a/test/test_index/idx_title.sbx b/test/test_index/idx_title.sbx
new file mode 100644
index 00000000..5cc83540
--- /dev/null
+++ b/test/test_index/idx_title.sbx
@@ -0,0 +1,22 @@
+\begin{idxblock}{C}
+  \idxentry{
+                \indextitle{}{Caa}
+            }{
+                \hyperlink{song1-3.2}{3}
+            }  \idxentry{
+                \indextitle{}{Çab}
+            }{
+                \hyperlink{song1-2.2}{2}
+            }  \idxentry{
+                \indextitle{}{Cac}
+            }{
+                \hyperlink{song1-4.2}{4}
+            }
+\end{idxblock}
+\begin{idxblock}{M}
+  \idxentry{
+                \indextitle{}{My song}
+            }{
+                \hyperlink{song1-1.2}{1}
+            }
+\end{idxblock}
diff --git a/test/test_index/idx_title.sxd b/test/test_index/idx_title.sxd
new file mode 100644
index 00000000..f6ba287f
--- /dev/null
+++ b/test/test_index/idx_title.sxd
@@ -0,0 +1,13 @@
+TITLE INDEX DATA FILE
+My song
+1
+song1-1.2
+Çab
+2
+song1-2.2
+Caa
+3
+song1-3.2
+Cac
+4
+song1-4.2
diff --git a/test/test_index/test_index.py b/test/test_index/test_index.py
new file mode 100644
index 00000000..94748fc4
--- /dev/null
+++ b/test/test_index/test_index.py
@@ -0,0 +1,46 @@
+"""Tests for the index generation."""
+
+import codecs
+import glob
+import os
+import unittest
+
+from patacrep.index import process_sxd
+
+from .. import dynamic # pylint: disable=unused-import
+
+
+class FileTest(unittest.TestCase, metaclass=dynamic.DynamicTest):
+    """Test of the index generation.
+
+    For any given `foo.sxd`, it generates the index.
+    It controls that the generated file is equal to the one in `foo.sbx`.
+    """
+
+    @classmethod
+    def _iter_testmethods(cls):
+        """Iterate over dynamically generated test methods"""
+        for source in sorted(glob.glob(os.path.join(
+                os.path.dirname(__file__),
+                '*.sxd',
+            ))):
+            base = source[:-len(".sxd")]
+            yield (
+                "test_index_{}".format(os.path.basename(base)),
+                cls._create_index_test(base),
+                )
+
+    @classmethod
+    def _create_index_test(cls, base):
+        """Return a function that tests that `foo.sxd` produces the sbx file"""
+
+        def test_index(self):
+            """Test that `foo.sxd` produces the correct sbx file"""
+            generated_index = process_sxd(base + ".sxd").entries_to_str()
+            with codecs.open(base + ".sbx", "r", "utf-8") as control_index:
+                self.assertEqual(control_index.read(), generated_index, )
+
+        test_index.__doc__ = (
+            "Test that '{base}.sxd' produces the correct sbx file"""
+            ).format(base=os.path.basename(base))
+        return test_index