Electric rail transport began in Germany as early as the 1890s in the form of trams, which were either newly built or electrified. They were powered by direct current with a voltage of less than 1,000 volts. The first electrified German mainline railway was the Ammergaubahn in Bavaria, which was built for three-phase operation and opened in 1900. Due to technical problems, it was initially operated with steam and only when the line was bought by the LAG was it switched to single-phase alternating current. From January 1, 1905, railcars were used here and a few months later the first two-axle electric locomotive was used. A system with 5,000 volts and 16 hertz was used here until the 1950s. Electrical operation with 6,300 volts and 25 hertz was tested in Prussia in 1908.
A short time later, the system with 15,000 volts and 16⅔ hertz, which is still used today in German-speaking and Scandinavian countries, became established. The frequency is exactly one third of the normal frequency in the public power grid and was better suited to the state of the art at the time than the full 50 hertz. From 1910 onwards, several German states ran trials on individual lines, which formed the basis for the expansion of the electrified networks and the procurement of new types of electric traction vehicles.
In Prussia, a large-scale trial operation started on the Dessau-Bitterfeld line with three express and six freight locomotives, each with different electrical equipment. In the same year, the Baden State Railways used an electric locomotive on the Wiesentalbahn and Wehratalbahn, which was later reinforced by eleven more. In Bavaria and neighboring Tyrol, the first five electric passenger locomotives were used from 1912 on the Mittenwaldbahn between Garmisch-Partenkirchen and Innsbruck. The line is considered the first line with the current voltage of 15,000 volts. The Saxon State Railways stayed with the five-kilometre-long Klingenthal-Sachsenberg-Georgenthal narrow-gauge railway, which was operated with direct current.
During this time, one of the focal points in development was the selection of the optimal power transmission. In the beginning, most electric locomotives used one or two large electric motors or double motors, which transmitted their power to the axles via countershafts or connecting rods and coupling rods. This allowed limited cushioning of the motors and was technically feasible at the time. The single-axle drive with nose-suspended motors, which was widespread in other countries, was only used in a few slow freight locomotives in Germany. Quill drives, which were mass-produced by Westinghouse in the USA from 1912, were not initially able to establish themselves in Germany.
With electric locomotives for passenger and express trains, a design with three or four driven axles mounted in the frame and carrying axles at the ends prevailed. The power usually came from one large motor, which reached a stator diameter of up to 3.60 meters. The rod drive could be used at speeds of up to 120 km/h. With the Prussian ES 51 to 57, the later E 06, an hourly output of 2,780 kW was achieved in 1924. Other types of drive, such as the Buchli drive, which was popular in Switzerland, were only used on a few electric locomotives in Germany. In the absence of electrically heated cars, passenger trains were usually heated by oil or coal-fired steam boilers.
Locomotives were developed for freight trains that did not have carrying axles and could use the entire weight for traction. One design used bogies, with all axles of each bogie being driven by one motor. These could be placed in low hoods and drove a crankshaft between the axles, from which the power was transmitted via coupling rods. In Prussia, heavy six-axle freight locomotives were built, which consisted of two or three sections and also had a rod drive.