• The birth of an all-wheel-drive all-rounder.

Off the beaten track.

The path takes the vehicle into the woods: where the damp autumn leaves lie thick on the ground and the narrow tyres dig deep into the muddy soil. At the rear, a heavy stack of wood presses down on the loading area of this compact commercial vehicle. At the front, the cooler and engine reach out into the air – as yet without any protective bodywork. The temporary arrangement of the driver’s cab told all: this was a prototype grinding its way through the forest. And it managed it.

Tractor and van, implement carrier and prime mover: this was a truly multi-faceted machine that set off on the chilly morning of 9 October 1946 on its first test run. In 2021, the Unimog celebrated its 75th anniversary. Its inventors later christened the production vehicle the “Universal Motorised Working Machine” (UniMoG). This gave rise to the catchy abbreviation "Unimog" for the all-wheel drive tractor with four equally sized wheels, which became a world star. After its trip through the forest, the next challenge for the compact machine were the steep slopes of the Swabian Alb hills. This was a really tough test.

From the prototype to series production: during the test drives in 1946, chief designer Heinrich Rößler was personally behind the wheel. Standing next to the pre-production vehicle is Hans Zabel – he invented the name Unimog.

From the prototype to series production: during the test drives in 1946, chief designer Heinrich Rößler was personally behind the wheel. Standing next to the pre-production vehicle is Hans Zabel – he invented the name Unimog.

A stroke of genius for agricultural productivity.

The concept of a universal machine for agricultural applications emerged directly after the end of the Second World War. Initially, the company was separate from the then Daimler-Benz AG, but was equipped with a Mercedes-Benz engine. The idea came from two former engineers of the company, Albert Friedrich and Heinrich Rößler.

Albert Friedrich initiated the project. The innovative vehicle was intended to help increase the productivity of the agricultural sector in providing food – urgently needed during the shortage years of the mid to late 1940s. The project was put into practice in Schwäbisch Gmünd at the metal construction company Erhard & Söhne. From January 1946 on, Rößler developed what was to become the Unimog. In March 1946, Hans Zabel, the engineer responsible for purchasing in the team, came up with the name. 

An innovative solution for agriculture: the Unimog was “a tractor, working machine and van all in one.”

An innovative solution for agriculture: the Unimog was “a tractor, working machine and van all in one.”

The chief designer at the wheel during a test drive.

The technical demands were high: amongst other things, the concept called for all-wheel drive and differential locks for maximum off-road capability, twice the speed of an ordinary tractor on the road, a tonne of payload on the loading area at the rear and the ability to attach and power ancillary equipment at the front, centre and rear. These key characteristics made the Unimog unique.

Four prototype vehicles were built at Erhard & Söhne for testing purposes. These tests were a matter for the boss and, on 9 October 1946, Heinrich Rößler took the wheel of the first Chassis U1 in person. The results of the test drives were convincing from all aspects – the Unimog proved to be a stroke of genius. 

Series production: Mercedes-Benz OM 636 engine.

After development at Erhard & Söhne, the mechanical engineering company Boehringer in Göppingen took over production. The construction of the last two prototypes, the U5 and U6, also began in Schwäbisch Gmünd but they were completed in Göppingen. The prototype vehicles were fitted with the Mercedes-Benz M 136 petrol engine from the Mercedes-Benz 170 V (W 136) passenger car.

For series production, however, the brand with the star supplied the new, high-speed OM 636 diesel engine (28 kW/38 PS) as the power unit. In the interests of long-term durability, especially in the harshest conditions, the output was limited to 18 kW (25 PS) and a maximum engine speed of 2500 rpm for use in the Unimog. 

Unimog chassis of the 70200 model series, built by Boehringer in Göppingen from 1949 to 1951.

Unimog chassis of the 70200 model series, built by Boehringer in Göppingen from 1949 to 1951.

Enthusiastic customers not only from agricultural circles.

In 1948, the Unimog made its debut at the first DLG agricultural fair after the Second World War in Frankfurt am Main. The Universal Motorised Working Machine fascinated the experts – not only those from agriculture and forestry.

The construction industry, logistics, fire brigades and many other sectors also immediately recognised the advantages of the Unimog. Right from the start, it covered a very wide range of applications that went far beyond agriculture. 

The star of the show: the Unimog made its trade fair debut appearance at the DLG agricultural trade fair in Frankfurt am Main at the end of August 1948. The sensational new concept impressed the public among other things due to the variety of attachments.

The star of the show: the Unimog made its trade fair debut appearance at the DLG agricultural trade fair in Frankfurt am Main at the end of August 1948. The sensational new concept impressed the public among other things due to the variety of attachments.

Mercedes star and bull’s head emblem.

The first 600 Unimog vehicles produced bore the bull’s head as Boehringer’s trademark. Then, in the summer of 1950, the then Daimler-Benz AG decided to take over the manufacture, distribution and development of the Unimog.

From June 1951 the Mercedes-Benz all-wheel-drive all-rounder was built at the Gaggenau plant and, from 1953, the new 401 model series also sported the Mercedes star in its cooler. Since then, this has been a worldwide success story  that has continued over numerous model series to this day.

The vehicle went into series production: the illustration in the brochure from 1951 showed the standard Unimog in its element working in the fields.

The vehicle went into series production: the illustration in the brochure from 1951 showed the standard Unimog in its element working in the fields.

Universally ready for the future.

Seventy-five years after the start of testing of the first Unimog chassis, the concept of the Universal Motorised Working Machine is as current now as it was in 1946.

This has been ensured over the past decades by continuous further development in various model series – right up to the current range with the Unimog implement carrier and the all-terrain Unimog.

A colourful history: Unimog vehicles from a range of model series and from different eras. Photo showing the Mercedes-Benz Classic Insight “70 years of the Unimog”, in September 2016.

A colourful history: Unimog vehicles from a range of model series and from different eras. Photo showing the Mercedes-Benz Classic Insight “70 years of the Unimog”, in September 2016.

Image gallery.