diff --git a/settings/Controller/PersonalController.php b/settings/Controller/PersonalController.php
new file mode 100644
index 00000000000..f9c67575466
--- /dev/null
+++ b/settings/Controller/PersonalController.php
@@ -0,0 +1,86 @@
+<?php
+/**
+ * @copyright  Roeland Jago Douma <roeland@famdouma.nl>
+ *
+ * @author Roeland Jago Douma <roeland@famdouma.nl>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+namespace OC\Settings\Controller;
+
+use OCP\AppFramework\Controller;
+use OCP\AppFramework\Http;
+use OCP\AppFramework\Http\JSONResponse;
+use OCP\IConfig;
+use OCP\IL10N;
+use OCP\IRequest;
+use OCP\L10N\IFactory;
+
+class PersonalController extends Controller {
+	/** @var IFactory */
+	private $l10nFactory;
+
+	/** @var string */
+	private $userId;
+
+	/** @var IConfig */
+	private $config;
+
+	/** @var IL10N */
+	private $l;
+
+	/**
+	 * PersonalController constructor.
+	 *
+	 * @param string $appName
+	 * @param IRequest $request
+	 * @param IFactory $l10nFactory
+	 * @param $userId
+	 * @param IConfig $config
+	 * @param IL10N $l
+	 */
+	public function __construct($appName,
+								IRequest $request,
+								IFactory $l10nFactory,
+								$userId,
+								IConfig $config,
+								IL10N $l) {
+		parent::__construct($appName, $request);
+
+		$this->l10nFactory = $l10nFactory;
+		$this->userId = $userId;
+		$this->config = $config;
+		$this->l = $l;
+	}
+
+	/**
+	 * @NoAdminRequired
+	 * @param string $lang
+	 * @return JSONResponse
+	 */
+	public function setLanguage($lang) {
+		if ($lang !== '') {
+			$languagesCodes = $this->l10nFactory->findAvailableLanguages();
+			if (array_search($lang, $languagesCodes) || $lang === 'en') {
+				$this->config->setUserValue($this->userId, 'core', 'lang', $lang);
+				return new JSONResponse([]);
+			}
+		}
+
+		return new JSONResponse(['message' => $this->l->t('Invalid request')], Http::STATUS_BAD_REQUEST);
+	}
+}
diff --git a/tests/Settings/Controller/PersonalControllerTest.php b/tests/Settings/Controller/PersonalControllerTest.php
new file mode 100644
index 00000000000..a1b727629bf
--- /dev/null
+++ b/tests/Settings/Controller/PersonalControllerTest.php
@@ -0,0 +1,122 @@
+<?php
+/**
+ *
+ *
+ * @author Roeland Jago Douma <roeland@famdouma.nl>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+namespace Test\Settings\Controller;
+
+use OC\Settings\Controller\PersonalController;
+use OCP\AppFramework\Http;
+use OCP\AppFramework\Http\JSONResponse;
+use OCP\IConfig;
+use OCP\IL10N;
+use OCP\IRequest;
+use OCP\L10N\IFactory;
+
+class PersonalControllerTest extends \Test\TestCase {
+
+	/** @var IFactory|\PHPUnit_Framework_MockObject_MockObject */
+	private $l10nFactory;
+	/** @var IConfig|\PHPUnit_Framework_MockObject_MockObject */
+	private $config;
+	/** @var PersonalController */
+	private $controller;
+	/** @var IL10N */
+	private $l;
+
+	public function setUp() {
+		parent::setUp();
+
+		$this->l10nFactory = $this->createMock(IFactory::class);
+		$this->config = $this->createMock(IConfig::class);
+		$this->l = $this->createMock(IL10N::class);
+
+		$this->l->method('t')
+			->will($this->returnCallback(function ($text, $parameters = []) {
+				return vsprintf($text, $parameters);
+			}));
+
+		$this->controller = new PersonalController(
+			'settings',
+			$this->createMock(IRequest::class),
+			$this->l10nFactory,
+			'user',
+			$this->config,
+			$this->l
+		);
+	}
+
+	public function testSetLanguage() {
+		$this->l10nFactory->method('findAvailableLanguages')
+			->willReturn(['aa', 'bb', 'cc']);
+		$this->config->expects($this->once())
+			->method('setUserValue')
+			->with(
+				$this->equalTo('user'),
+				$this->equalTo('core'),
+				$this->equalTo('lang'),
+				$this->equalTo('bb')
+			);
+
+		$resp = $this->controller->setLanguage('bb');
+		$expected = new JSONResponse([]);
+		$this->assertEquals($expected, $resp);
+	}
+
+	public function testSetLanguageEn() {
+		$this->l10nFactory->method('findAvailableLanguages')
+			->willReturn(['aa', 'bb', 'cc']);
+		$this->config->expects($this->once())
+			->method('setUserValue')
+			->with(
+				$this->equalTo('user'),
+				$this->equalTo('core'),
+				$this->equalTo('lang'),
+				$this->equalTo('en')
+			);
+
+		$resp = $this->controller->setLanguage('en');
+		$expected = new JSONResponse([]);
+		$this->assertEquals($expected, $resp);
+	}
+
+	public function testSetLanguageFails() {
+		$this->l10nFactory->method('findAvailableLanguages')
+			->willReturn(['aa', 'bb', 'cc']);
+		$this->config->expects($this->never())
+			->method('setUserValue');
+
+		$resp = $this->controller->setLanguage('dd');
+		$expected = new JSONResponse(['message' => 'Invalid request'], Http::STATUS_BAD_REQUEST);
+		$this->assertEquals($expected, $resp);
+	}
+
+
+	public function testSetLanguageEmpty() {
+		$this->l10nFactory->method('findAvailableLanguages')
+			->willReturn(['aa', 'bb', 'cc']);
+		$this->config->expects($this->never())
+			->method('setUserValue');
+
+		$resp = $this->controller->setLanguage('');
+		$expected = new JSONResponse(['message' => 'Invalid request'], Http::STATUS_BAD_REQUEST);
+		$this->assertEquals($expected, $resp);
+	}
+}