diff --git a/core/src/main/java/org/elasticsearch/common/util/LocaleUtils.java b/core/src/main/java/org/elasticsearch/common/util/LocaleUtils.java
index cd83b22b28b..d447bc0567d 100644
--- a/core/src/main/java/org/elasticsearch/common/util/LocaleUtils.java
+++ b/core/src/main/java/org/elasticsearch/common/util/LocaleUtils.java
@@ -103,15 +103,4 @@ public class LocaleUtils {
             throw new IllegalArgumentException("Locales can have at most 3 parts but got " + parts.length + ": " + Arrays.asList(parts));
         }
     }
-
-    /**
-     * Validate a {@link Locale} object
-     */
-    public static boolean isValid(Locale locale) {
-        try {
-            return locale.getISO3Language() != null && locale.getISO3Country() != null;
-        } catch (MissingResourceException e) {
-            return false;
-        }
-    }
 }
diff --git a/modules/ingest-common/src/main/java/org/elasticsearch/ingest/common/DateProcessor.java b/modules/ingest-common/src/main/java/org/elasticsearch/ingest/common/DateProcessor.java
index f65fd382b1e..4dec8f53d3f 100644
--- a/modules/ingest-common/src/main/java/org/elasticsearch/ingest/common/DateProcessor.java
+++ b/modules/ingest-common/src/main/java/org/elasticsearch/ingest/common/DateProcessor.java
@@ -111,7 +111,6 @@ public final class DateProcessor extends AbstractProcessor {
 
     public static final class Factory implements Processor.Factory {
 
-        @SuppressWarnings("unchecked")
         public DateProcessor create(Map<String, Processor.Factory> registry, String processorTag,
                                     Map<String, Object> config) throws Exception {
             String field = ConfigurationUtils.readStringProperty(TYPE, processorTag, config, "field");
@@ -119,16 +118,9 @@ public final class DateProcessor extends AbstractProcessor {
             String timezoneString = ConfigurationUtils.readOptionalStringProperty(TYPE, processorTag, config, "timezone");
             DateTimeZone timezone = timezoneString == null ? DateTimeZone.UTC : DateTimeZone.forID(timezoneString);
             String localeString = ConfigurationUtils.readOptionalStringProperty(TYPE, processorTag, config, "locale");
-            Locale locale = Locale.ENGLISH;
+            Locale locale = Locale.ROOT;
             if (localeString != null) {
-                try {
-                    locale = (new Locale.Builder()).setLanguageTag(localeString).build();
-                } catch (IllformedLocaleException e) {
-                    throw new IllegalArgumentException("Invalid language tag specified: " + localeString);
-                }
-                if (!LocaleUtils.isValid(locale)) {
-                    throw new IllegalArgumentException("Invalid language tag specified: " + localeString);
-                }
+                locale = LocaleUtils.parse(localeString);
             }
             List<String> formats = ConfigurationUtils.readList(TYPE, processorTag, config, "formats");
             return new DateProcessor(processorTag, timezone, locale, field, formats, targetField);
diff --git a/modules/ingest-common/src/test/java/org/elasticsearch/ingest/common/DateProcessorFactoryTests.java b/modules/ingest-common/src/test/java/org/elasticsearch/ingest/common/DateProcessorFactoryTests.java
index 6bb3887f670..f722f658bd1 100644
--- a/modules/ingest-common/src/test/java/org/elasticsearch/ingest/common/DateProcessorFactoryTests.java
+++ b/modules/ingest-common/src/test/java/org/elasticsearch/ingest/common/DateProcessorFactoryTests.java
@@ -46,7 +46,7 @@ public class DateProcessorFactoryTests extends ESTestCase {
         assertThat(processor.getField(), equalTo(sourceField));
         assertThat(processor.getTargetField(), equalTo(DateProcessor.DEFAULT_TARGET_FIELD));
         assertThat(processor.getFormats(), equalTo(Collections.singletonList("dd/MM/yyyyy")));
-        assertThat(processor.getLocale(), equalTo(Locale.ENGLISH));
+        assertThat(processor.getLocale(), equalTo(Locale.ROOT));
         assertThat(processor.getTimezone(), equalTo(DateTimeZone.UTC));
     }
 
@@ -95,7 +95,7 @@ public class DateProcessorFactoryTests extends ESTestCase {
     }
 
     public void testParseInvalidLocale() throws Exception {
-        String[] locales = new String[] { "invalid_locale", "english", "xy", "en-XY" };
+        String[] locales = new String[] { "invalid_locale", "english", "xy", "xy-US" };
         for (String locale : locales) {
             DateProcessor.Factory factory = new DateProcessor.Factory();
             Map<String, Object> config = new HashMap<>();
@@ -103,12 +103,22 @@ public class DateProcessorFactoryTests extends ESTestCase {
             config.put("field", sourceField);
             config.put("formats", Collections.singletonList("dd/MM/yyyyy"));
             config.put("locale", locale);
-            try {
-                factory.create(null, null, config);
-                fail("should fail with invalid locale");
-            } catch(IllegalArgumentException e) {
-                assertThat(e.getMessage(), equalTo("Invalid language tag specified: " + locale));
-            }
+            IllegalArgumentException e = expectThrows(IllegalArgumentException.class,
+                    () -> factory.create(null, null, config));
+            assertThat(e.getMessage(), equalTo("Unknown language: " + locale.split("[_-]")[0]));
+        }
+
+        locales = new String[] { "en-XY", "en-Canada" };
+        for (String locale : locales) {
+            DateProcessor.Factory factory = new DateProcessor.Factory();
+            Map<String, Object> config = new HashMap<>();
+            String sourceField = randomAlphaOfLengthBetween(1, 10);
+            config.put("field", sourceField);
+            config.put("formats", Collections.singletonList("dd/MM/yyyyy"));
+            config.put("locale", locale);
+            IllegalArgumentException e = expectThrows(IllegalArgumentException.class,
+                    () -> factory.create(null, null, config));
+            assertThat(e.getMessage(), equalTo("Unknown country: " + locale.split("[_-]")[1]));
         }
     }