diff --git a/CHANGELOG.txt b/CHANGELOG.txt
index 563d973e2..1f8431c53 100644
--- a/CHANGELOG.txt
+++ b/CHANGELOG.txt
@@ -15,6 +15,7 @@ Changelog
  * Fix: Wagtail's middleware classes are now compatible with Django 1.10's new-style middleware (Karl Hobley)
  * Fix: The `Pages.can_create_at` method is now checked in the create page view (Mikalai Radchuk)
  * Fix: Fixed regression on Django 1.10.1 causing Page subclasses to fail to use PageManager (Matt Westcott)
+ * Fix: ChoiceBlocks with lazy translations as option labels no longer break Elasticsearch indexing (Matt Westcott)
 
 
 1.6 (15.08.2016)
diff --git a/docs/releases/1.6.1.rst b/docs/releases/1.6.1.rst
index f81b1b048..4649be2fe 100644
--- a/docs/releases/1.6.1.rst
+++ b/docs/releases/1.6.1.rst
@@ -16,6 +16,7 @@ Bug fixes
 * Wagtail's middleware classes are now compatible with Django 1.10's `new-style middleware <https://docs.djangoproject.com/en/1.10/releases/1.10/#new-style-middleware>`_ (Karl Hobley)
 * The :meth:`~wagtail.wagtailcore.models.Page.can_create_at` method is now checked in the create page view (Mikalai Radchuk)
 * Fixed regression on Django 1.10.1 causing Page subclasses to fail to use PageManager (Matt Westcott)
+* ChoiceBlocks with lazy translations as option labels no longer break Elasticsearch indexing (Matt Westcott)
 
 
 Upgrade considerations
diff --git a/wagtail/wagtailcore/blocks/field_block.py b/wagtail/wagtailcore/blocks/field_block.py
index cce57eb4e..71af4b90b 100644
--- a/wagtail/wagtailcore/blocks/field_block.py
+++ b/wagtail/wagtailcore/blocks/field_block.py
@@ -370,10 +370,10 @@ class ChoiceBlock(FieldBlock):
                 # This is an optgroup, so look inside the group for options
                 for k2, v2 in v:
                     if value == k2 or text_value == force_text(k2):
-                        return [k, v2]
+                        return [force_text(k), force_text(v2)]
             else:
                 if value == k or text_value == force_text(k):
-                    return [v]
+                    return [force_text(v)]
         return []  # Value was not found in the list of choices
 
     class Meta:
diff --git a/wagtail/wagtailcore/tests/test_blocks.py b/wagtail/wagtailcore/tests/test_blocks.py
index 76f34f631..e9029bdd2 100644
--- a/wagtail/wagtailcore/tests/test_blocks.py
+++ b/wagtail/wagtailcore/tests/test_blocks.py
@@ -3,10 +3,12 @@ from __future__ import absolute_import, unicode_literals
 
 import base64
 import collections
+import json
 import unittest
 import warnings
 from decimal import Decimal
 
+# non-standard import name for ugettext_lazy, to prevent strings from being picked up for translation
 from django import forms
 from django.core.exceptions import ValidationError
 from django.forms.utils import ErrorList
@@ -14,6 +16,7 @@ from django.template.loader import render_to_string
 from django.test import SimpleTestCase, TestCase
 from django.utils.html import format_html
 from django.utils.safestring import SafeData, mark_safe
+from django.utils.translation import ugettext_lazy as __
 
 from wagtail.tests.testapp.blocks import LinkBlock as CustomLinkBlock
 from wagtail.tests.testapp.blocks import SectionBlock
@@ -608,6 +611,34 @@ class TestChoiceBlock(unittest.TestCase):
         ])
         self.assertEqual(block.get_searchable_content('three'), [])
 
+    def test_searchable_content_with_lazy_translation(self):
+        block = blocks.ChoiceBlock(choices=[
+            ('choice-1', __("Choice 1")),
+            ('choice-2', __("Choice 2")),
+        ])
+        result = block.get_searchable_content("choice-1")
+        # result must survive JSON (de)serialisation, which is not the case for
+        # lazy translation objects
+        result = json.loads(json.dumps(result))
+        self.assertEqual(result, ["Choice 1"])
+
+    def test_optgroup_searchable_content_with_lazy_translation(self):
+        block = blocks.ChoiceBlock(choices=[
+            (__('Section 1'), [
+                ('1-1', __("Block 1")),
+                ('1-2', __("Block 2")),
+            ]),
+            (__('Section 2'), [
+                ('2-1', __("Block 1")),
+                ('2-2', __("Block 2")),
+            ]),
+        ])
+        result = block.get_searchable_content("2-2")
+        # result must survive JSON (de)serialisation, which is not the case for
+        # lazy translation objects
+        result = json.loads(json.dumps(result))
+        self.assertEqual(result, ["Section 2", "Block 2"])
+
 
 class TestRawHTMLBlock(unittest.TestCase):
     def test_get_default_with_fallback_value(self):