diff --git a/frappe/tests/test_translate.py b/frappe/tests/test_translate.py
index f51f31d509..717b18ced8 100644
--- a/frappe/tests/test_translate.py
+++ b/frappe/tests/test_translate.py
@@ -1,13 +1,27 @@
-# Copyright (c) 2015, Frappe Technologies Pvt. Ltd. and Contributors
+# Copyright (c) 2021, Frappe Technologies Pvt. Ltd. and Contributors
 # MIT License. See license.txt
-import frappe, unittest, os
+import os
+import unittest
+from random import choices
+from unittest.mock import patch
+
+import frappe
 import frappe.translate
 from frappe import _
+from frappe.auth import HTTPRequest
+from frappe.translate import get_parent_language
+from frappe.utils import set_request
 
 dirname = os.path.dirname(__file__)
 translation_string_file = os.path.join(dirname, 'translation_test_file.txt')
+first_lang, second_lang, third_lang, fourth_lang, fifth_lang = choices(
+	frappe.get_all("Language", pluck="name"), k=5
+)
 
 class TestTranslate(unittest.TestCase):
+	def tearDown(self):
+		frappe.form_dict.pop("_lang", None)
+
 	def test_extract_message_from_file(self):
 		data = frappe.translate.get_messages_from_file(translation_string_file)
 		self.assertListEqual(data, expected_output)
@@ -20,6 +34,42 @@ class TestTranslate(unittest.TestCase):
 		finally:
 			frappe.local.lang = 'en'
 
+	def test_request_language_resolution_with_form_dict(self):
+		"""Test for frappe.translate.get_language
+
+		Case 1: frappe.form_dict._lang is set
+		"""
+
+		frappe.form_dict._lang = first_lang
+
+		with patch.object(frappe.translate, "get_preferred_language_cookie", return_value=second_lang):
+			set_request(method="POST", path="/", headers=[("Accept-Language", third_lang)])
+			HTTPRequest()
+
+		self.assertIn(frappe.local.lang, [first_lang, get_parent_language(first_lang)])
+
+	def test_request_language_resolution_with_cookie(self):
+		"""Test for frappe.translate.get_language
+
+		Case 2: frappe.form_dict._lang is not set, but preferred_language cookie is
+		"""
+
+		with patch.object(frappe.translate, "get_preferred_language_cookie", return_value=second_lang):
+			set_request(method="POST", path="/", headers=[("Accept-Language", third_lang)])
+			HTTPRequest()
+
+		self.assertIn(frappe.local.lang, [second_lang, get_parent_language(second_lang)])
+
+	def test_request_language_resolution_with_request_header(self):
+		"""Test for frappe.translate.get_language
+
+		Case 3: frappe.form_dict._lang & preferred_language cookie is not set, but Accept-Language header is
+		"""
+		set_request(method="POST", path="/", headers=[("Accept-Language", third_lang)])
+		HTTPRequest()
+		self.assertIn(frappe.local.lang, [third_lang, get_parent_language(third_lang)])
+
+
 expected_output = [
 	('apps/frappe/frappe/tests/translation_test_file.txt', 'Warning: Unable to find {0} in any table related to {1}', 'This is some context', 2),
 	('apps/frappe/frappe/tests/translation_test_file.txt', 'Warning: Unable to find {0} in any table related to {1}', None, 4),
diff --git a/frappe/translate.py b/frappe/translate.py
index ce4c3abf3d..d5916f1761 100644
--- a/frappe/translate.py
+++ b/frappe/translate.py
@@ -44,7 +44,7 @@ def get_language(lang_list: List = None) -> str:
 	lang_set = set(lang_list or get_all_languages() or [])
 
 	# fetch language from cookie
-	preferred_language_cookie = frappe.request.cookies.get('preferred_language')
+	preferred_language_cookie = get_preferred_language_cookie()
 
 	if preferred_language_cookie:
 		if preferred_language_cookie in lang_set:
@@ -906,3 +906,6 @@ def get_all_languages(with_language_name=False):
 @frappe.whitelist(allow_guest=True)
 def set_preferred_language_cookie(preferred_language):
 	frappe.local.cookie_manager.set_cookie("preferred_language", preferred_language)
+
+def get_preferred_language_cookie():
+	return frappe.request.cookies.get("preferred_language")