The engines later designated as class G 1 were light tender locomotives for freight service. They were ordered by the Prussian Ostbahn, as they had extensive branch lines on which the range of tank locomotives would not have been sufficient. These were locomotives with two coupled axles and no carrying axles, which were powered by a two-cylinder saturated engine.
The first production lot consisted of 44 examples and was delivered between 1878 and 1879. Later, under the administration of the state railways, a further need for these locomotives was identified. Therefore, a second series of 49 engines was purchased, which lasted from 1887 to 1898. The newer locos were a little lighter than the original ones, but could still produce the same power. This was achieved by increasing the boiler pressure from 10 to 12 bars and installing cylinders with a smaller diameter but slightly longer piston stroke.
From 1905 the locomotives were given the designation G 1 in order to be able to classify them into a specific type according to their purpose. Until then, the locomotives of the Ostbahn were only provided with numbers, the range of which gave little information about the type. The decommissioning then finally took place at the beginning of the twenties.