diff --git a/README.md b/README.md
index 3930bf0cd22..e409ae8e648 100644
--- a/README.md
+++ b/README.md
@@ -87,6 +87,7 @@ Do not use 20.x.x if you need IE support.
 - add redis as a valid option for `global/session_save` #1513
 - possibility to disable global search in backend #1532
 - reduce needless saves by avoiding setting `_hasDataChanges` flag #2066
+- removed support for `global/sales/old_fields_map` defined in XML #921
 
 For full list of changes, you can [compare tags](https://github.com/OpenMage/magento-lts/compare/1.9.4.x...20.0).
 
diff --git a/app/code/core/Mage/Catalog/Model/Product.php b/app/code/core/Mage/Catalog/Model/Product.php
index 03b59086312..a3f3875948b 100644
--- a/app/code/core/Mage/Catalog/Model/Product.php
+++ b/app/code/core/Mage/Catalog/Model/Product.php
@@ -362,7 +362,6 @@ protected function _construct()
      */
     protected function _initOldFieldsMap()
     {
-        $this->_oldFieldsMap = Mage::helper('catalog')->getOldFieldMap();
         return $this;
     }
 
diff --git a/app/code/core/Mage/CatalogInventory/Model/Stock/Item.php b/app/code/core/Mage/CatalogInventory/Model/Stock/Item.php
index eb54bd5e7cf..5dbef74b415 100644
--- a/app/code/core/Mage/CatalogInventory/Model/Stock/Item.php
+++ b/app/code/core/Mage/CatalogInventory/Model/Stock/Item.php
@@ -177,6 +177,7 @@ protected function _construct()
      */
     protected function _initOldFieldsMap()
     {
+        // pre 1.6 fields names, old => new
         $this->_oldFieldsMap = array(
             'stock_status_changed_automatically' => 'stock_status_changed_auto',
             'use_config_enable_qty_increments'   => 'use_config_enable_qty_inc'
diff --git a/app/code/core/Mage/Sales/Model/Order.php b/app/code/core/Mage/Sales/Model/Order.php
index ad23b81ec2b..3fa9ab22c51 100644
--- a/app/code/core/Mage/Sales/Model/Order.php
+++ b/app/code/core/Mage/Sales/Model/Order.php
@@ -526,7 +526,12 @@ protected function _construct()
      */
     protected function _initOldFieldsMap()
     {
-        $this->_oldFieldsMap = Mage::helper('sales')->getOldFieldMap('order');
+        // pre 1.6 fields names, old => new
+        $this->_oldFieldsMap = [
+            'payment_authorization_expiration' => 'payment_auth_expiration',
+            'forced_do_shipment_with_invoice' => 'forced_shipment_with_invoice',
+            'base_shipping_hidden_tax_amount' => 'base_shipping_hidden_tax_amnt',
+        ];
         return $this;
     }
 
diff --git a/app/code/core/Mage/Sales/Model/Order/Address.php b/app/code/core/Mage/Sales/Model/Order/Address.php
index 8b259debf63..cd9dddc41cc 100644
--- a/app/code/core/Mage/Sales/Model/Order/Address.php
+++ b/app/code/core/Mage/Sales/Model/Order/Address.php
@@ -112,7 +112,6 @@ protected function _construct()
      */
     protected function _initOldFieldsMap()
     {
-        $this->_oldFieldsMap = Mage::helper('sales')->getOldFieldMap('order_address');
         return $this;
     }
 
diff --git a/app/code/core/Mage/Sales/Model/Order/Creditmemo.php b/app/code/core/Mage/Sales/Model/Order/Creditmemo.php
index f6743a80d14..91f1c0fbbf9 100644
--- a/app/code/core/Mage/Sales/Model/Order/Creditmemo.php
+++ b/app/code/core/Mage/Sales/Model/Order/Creditmemo.php
@@ -224,7 +224,6 @@ protected function _construct()
      */
     protected function _initOldFieldsMap()
     {
-        $this->_oldFieldsMap = Mage::helper('sales')->getOldFieldMap('order_creditmemo');
         return $this;
     }
 
diff --git a/app/code/core/Mage/Sales/Model/Order/Creditmemo/Item.php b/app/code/core/Mage/Sales/Model/Order/Creditmemo/Item.php
index 7cae8b9405c..0cebb04ba63 100644
--- a/app/code/core/Mage/Sales/Model/Order/Creditmemo/Item.php
+++ b/app/code/core/Mage/Sales/Model/Order/Creditmemo/Item.php
@@ -153,7 +153,10 @@ public function setCreditmemo(Mage_Sales_Model_Order_Creditmemo $creditmemo)
      */
     protected function _initOldFieldsMap()
     {
-        $this->_oldFieldsMap = Mage::helper('sales')->getOldFieldMap('creditmemo_item');
+        // pre 1.6 fields names, old => new
+        $this->_oldFieldsMap = [
+            'base_weee_tax_applied_row_amount' => 'base_weee_tax_applied_row_amnt',
+        ];
         return $this;
     }
 
diff --git a/app/code/core/Mage/Sales/Model/Order/Invoice.php b/app/code/core/Mage/Sales/Model/Order/Invoice.php
index e1b6ffd51da..fccd1718753 100644
--- a/app/code/core/Mage/Sales/Model/Order/Invoice.php
+++ b/app/code/core/Mage/Sales/Model/Order/Invoice.php
@@ -223,7 +223,6 @@ protected function _construct()
      */
     protected function _initOldFieldsMap()
     {
-        $this->_oldFieldsMap = Mage::helper('sales')->getOldFieldMap('order_invoice');
         return $this;
     }
 
diff --git a/app/code/core/Mage/Sales/Model/Order/Invoice/Item.php b/app/code/core/Mage/Sales/Model/Order/Invoice/Item.php
index f931beaa9a4..cac7347c837 100644
--- a/app/code/core/Mage/Sales/Model/Order/Invoice/Item.php
+++ b/app/code/core/Mage/Sales/Model/Order/Invoice/Item.php
@@ -125,7 +125,10 @@ public function _construct()
      */
     protected function _initOldFieldsMap()
     {
-        $this->_oldFieldsMap = Mage::helper('sales')->getOldFieldMap('invoice_item');
+        // pre 1.6 fields names, old => new
+        $this->_oldFieldsMap = [
+            'base_weee_tax_applied_row_amount' => 'base_weee_tax_applied_row_amnt',
+        ];
         return $this;
     }
     /**
diff --git a/app/code/core/Mage/Sales/Model/Order/Item.php b/app/code/core/Mage/Sales/Model/Order/Item.php
index 33627c6aa90..0e6f85caaeb 100644
--- a/app/code/core/Mage/Sales/Model/Order/Item.php
+++ b/app/code/core/Mage/Sales/Model/Order/Item.php
@@ -246,7 +246,10 @@ protected function _construct()
      */
     protected function _initOldFieldsMap()
     {
-        $this->_oldFieldsMap = Mage::helper('sales')->getOldFieldMap('order_item');
+        // pre 1.6 fields names, old => new
+        $this->_oldFieldsMap = [
+            'base_weee_tax_applied_row_amount' => 'base_weee_tax_applied_row_amnt',
+        ];
         return $this;
     }
 
diff --git a/app/code/core/Mage/Sales/Model/Order/Shipment.php b/app/code/core/Mage/Sales/Model/Order/Shipment.php
index 22057b2e946..f0eb59b4248 100644
--- a/app/code/core/Mage/Sales/Model/Order/Shipment.php
+++ b/app/code/core/Mage/Sales/Model/Order/Shipment.php
@@ -127,7 +127,6 @@ protected function _construct()
      */
     protected function _initOldFieldsMap()
     {
-        $this->_oldFieldsMap = Mage::helper('sales')->getOldFieldMap('order_shipment');
         return $this;
     }
 
diff --git a/app/code/core/Mage/Sales/Model/Quote.php b/app/code/core/Mage/Sales/Model/Quote.php
index 55ce1a5acb1..b9b8bdd2c5c 100644
--- a/app/code/core/Mage/Sales/Model/Quote.php
+++ b/app/code/core/Mage/Sales/Model/Quote.php
@@ -262,7 +262,6 @@ protected function _construct()
      */
     protected function _initOldFieldsMap()
     {
-        $this->_oldFieldsMap = Mage::helper('sales')->getOldFieldMap('quote');
         return $this;
     }
 
diff --git a/app/code/core/Mage/Sales/Model/Quote/Address.php b/app/code/core/Mage/Sales/Model/Quote/Address.php
index d8e7bf741c2..7fe6002d775 100644
--- a/app/code/core/Mage/Sales/Model/Quote/Address.php
+++ b/app/code/core/Mage/Sales/Model/Quote/Address.php
@@ -321,7 +321,6 @@ protected function _construct()
      */
     protected function _initOldFieldsMap()
     {
-        $this->_oldFieldsMap = Mage::helper('sales')->getOldFieldMap('quote_address');
         return $this;
     }
 
diff --git a/app/code/core/Mage/Sales/Model/Quote/Item.php b/app/code/core/Mage/Sales/Model/Quote/Item.php
index 72b19e1bbb3..a3d0c7bb2d9 100644
--- a/app/code/core/Mage/Sales/Model/Quote/Item.php
+++ b/app/code/core/Mage/Sales/Model/Quote/Item.php
@@ -247,7 +247,6 @@ protected function _construct()
      */
     protected function _initOldFieldsMap()
     {
-        $this->_oldFieldsMap = Mage::helper('sales')->getOldFieldMap('quote_item');
         return $this;
     }
 
diff --git a/app/code/core/Mage/Sales/etc/config.xml b/app/code/core/Mage/Sales/etc/config.xml
index c83e510ade0..b62cf944a4e 100644
--- a/app/code/core/Mage/Sales/etc/config.xml
+++ b/app/code/core/Mage/Sales/etc/config.xml
@@ -1198,13 +1198,6 @@
             </product>
         </catalog>
         <sales>
-            <old_fields_map>
-                <order>
-                    <payment_authorization_expiration>payment_auth_expiration</payment_authorization_expiration>
-                    <forced_do_shipment_with_invoice>forced_shipment_with_invoice</forced_do_shipment_with_invoice>
-                    <base_shipping_hidden_tax_amount>base_shipping_hidden_tax_amnt</base_shipping_hidden_tax_amount>
-                </order>
-            </old_fields_map>
             <quote>
                 <totals>
                     <nominal>
diff --git a/app/code/core/Mage/Weee/etc/config.xml b/app/code/core/Mage/Weee/etc/config.xml
index af8fa12125b..7c9f74c1fdd 100644
--- a/app/code/core/Mage/Weee/etc/config.xml
+++ b/app/code/core/Mage/Weee/etc/config.xml
@@ -225,17 +225,6 @@
                     </weee>
                 </totals>
             </order_creditmemo>
-            <old_fields_map>
-                <order_item>
-                    <base_weee_tax_applied_row_amount>base_weee_tax_applied_row_amnt</base_weee_tax_applied_row_amount>
-                </order_item>
-                <invoice_item>
-                    <base_weee_tax_applied_row_amount>base_weee_tax_applied_row_amnt</base_weee_tax_applied_row_amount>
-                </invoice_item>
-                <creditmemo_item>
-                    <base_weee_tax_applied_row_amount>base_weee_tax_applied_row_amnt</base_weee_tax_applied_row_amount>
-                </creditmemo_item>
-            </old_fields_map>
         </sales>
     </global>
     <adminhtml>