diff --git a/oxrlib/loaders.py b/oxrlib/loaders.py
index 3e4d22b10d7f3b34c24399c30ba86356632d3c23..e839dddcbb9c18748fc020fdae6f2cd04a373b06 100644
--- a/oxrlib/loaders.py
+++ b/oxrlib/loaders.py
@@ -1,3 +1,8 @@
+import cgi
+import io
+import urllib.request
+import urllib.parse
+
 class LoaderError(Exception):
     pass
 
@@ -25,3 +30,48 @@ class FileCache:
             return path.open()
         except FileNotFoundError as error:
             raise LoaderNoDataError(path) from error
+
+
+class OXRAPIRequest:
+    DEFAULT_API_ROOT = 'https://openexchangerates.org/api/'
+    DEFAULT_RESPONSE_ENCODING = 'utf-8'
+
+    def __init__(self, app_id, api_root=None, *, open_func=urllib.request.urlopen):
+        self.api_root = self.DEFAULT_API_ROOT if api_root is None else api_root
+        self.app_id = app_id
+        self.open_url = open_func
+
+    def _get_response_encoding(self, response, default=None):
+        try:
+            content_type = response.getheader('Content-Type', 'application/json')
+            _, ct_options = cgi.parse_header(content_type)
+            encoding = ct_options['charset']
+        except (KeyError, ValueError):
+            encoding = self.DEFAULT_RESPONSE_ENCODING if default is None else default
+        return encoding
+
+    def _raw_query(self, url_tail, params):
+        url = '{}?{}'.format(
+            urllib.parse.urljoin(self.api_root, url_tail),
+            urllib.parse.urlencode(params),
+        )
+        response = self.open_url(url)
+        status_code = response.status
+        encoding = self._get_response_encoding(response)
+        response_body = io.TextIOWrapper(response, encoding=encoding)
+        if 200 <= status_code < 203:
+            return response_body
+        elif status_code == 404 or status_code == 410:
+            exc_class = LoaderNoDataError
+        elif status_code >= 500:
+            exc_class = LoaderSourceError
+        else:
+            exc_class = LoaderBadRequestError
+        with response_body:
+            raise exc_class(url, response_body.read(64 * 1024))
+
+    def historical(self, date, base):
+        return self._raw_query(
+            'historical/{}.json'.format(date.isoformat()),
+            {'app_id': self.app_id, 'base': base},
+        )