diff --git a/include/library.h b/include/library.h
index 856a3a9e..fa8f2426 100644
--- a/include/library.h
+++ b/include/library.h
@@ -106,7 +106,15 @@ class Filter {
     Filter& rejectTags(const Tags& tags);
 
     Filter& category(std::string category);
+
+    /**
+     *  Set the filter to only accept books in the specified language.
+     *
+     *  Multiple languages can be specified as a comma-separated list (in
+     *  which case a book in any of those languages will match).
+     */
     Filter& lang(std::string lang);
+
     Filter& publisher(std::string publisher);
     Filter& creator(std::string creator);
     Filter& maxSize(size_t size);
diff --git a/src/library.cpp b/src/library.cpp
index 508d7c8e..fb9fc035 100644
--- a/src/library.cpp
+++ b/src/library.cpp
@@ -535,9 +535,20 @@ Xapian::Query categoryQuery(const std::string& category)
   return Xapian::Query("XC" + normalizeText(category));
 }
 
-Xapian::Query langQuery(const std::string& lang)
+Xapian::Query langQuery(const std::string& commaSeparatedLanguageList)
 {
-  return Xapian::Query("L" + normalizeText(lang));
+  Xapian::Query q;
+  bool firstIteration = true;
+  for ( const auto& lang : kiwix::split(commaSeparatedLanguageList, ",") ) {
+    const Xapian::Query singleLangQuery("L" + normalizeText(lang));
+    if ( firstIteration ) {
+      q = singleLangQuery;
+      firstIteration = false;
+    } else {
+      q = Xapian::Query(Xapian::Query::OP_OR, q, singleLangQuery);
+    }
+  }
+  return q;
 }
 
 Xapian::Query publisherQuery(const std::string& publisher)
diff --git a/test/library_server.cpp b/test/library_server.cpp
index e5e330d6..ee20b954 100644
--- a/test/library_server.cpp
+++ b/test/library_server.cpp
@@ -344,10 +344,12 @@ TEST_F(LibraryServerTest, catalog_search_by_language)
       "  <id>12345678-90ab-cdef-1234-567890abcdef</id>\n"
       "  <title>Filtered zims (lang=eng,fra)</title>\n"
       "  <updated>YYYY-MM-DDThh:mm:ssZ</updated>\n"
-      "  <totalResults>0</totalResults>\n"
+      "  <totalResults>2</totalResults>\n"
       "  <startIndex>0</startIndex>\n"
-      "  <itemsPerPage>0</itemsPerPage>\n"
+      "  <itemsPerPage>2</itemsPerPage>\n"
       CATALOG_LINK_TAGS
+      RAY_CHARLES_CATALOG_ENTRY
+      CHARLES_RAY_CATALOG_ENTRY
       "</feed>\n"
     );
   }
@@ -727,9 +729,11 @@ TEST_F(LibraryServerTest, catalog_v2_entries_filtered_by_language)
       CATALOG_V2_ENTRIES_PREAMBLE("?lang=eng,fra")
       "  <title>Filtered Entries (lang=eng,fra)</title>\n"
       "  <updated>YYYY-MM-DDThh:mm:ssZ</updated>\n"
-      "  <totalResults>0</totalResults>\n"
+      "  <totalResults>2</totalResults>\n"
       "  <startIndex>0</startIndex>\n"
-      "  <itemsPerPage>0</itemsPerPage>\n"
+      "  <itemsPerPage>2</itemsPerPage>\n"
+      RAY_CHARLES_CATALOG_ENTRY
+      CHARLES_RAY_CATALOG_ENTRY
       "</feed>\n"
     );
   }