Upgrading Russian railways in 1956.

In 1956 the Russian Railways decided to use the 50 Hz 25 kW system for further electrification. A first line was built south of Moscow and experimental locomotives were ordered. To use the experience of Western European firms, fifty locomotives were ordered in France in 1959 and twenty locomotives in Germany in 1961. The French locomotives were built by Alsthom in three variants, two for goods trains and one for passenger trains. The German locomotives were built by Krupp together with Siemens. More 50 Hz 25 kW locomotives were built in Russia from 1961 onwards.