Despite its relatively recent association with LGB, garden railways were popularised in England during the earliest years of the 20th century using tin-plate models on Gauge 1 tracks (of which more later).  The hobby of Large Scale Railway Modelling in general declined sharply in the late 1930s being superseded initially by O gauge and then by the growing trend for smaller scales such as 00, HO, TT, N and ultimately Z.

It was not until LGB entered the market in the late 1960’s with a German variant of the old Gauge 1 (normally 1:32 scale) using the same 45mm gauge track but for trains modelled on European (and later American) narrow gauge prototypes in a rather unusual scale of 1:22.5.  In Europe this is often referred to as Gauge IIm (one metre width narrow gauge). Metre gauge is the most common narrow gauge found in Europe although there are many other variations.

Although 00 was fairly well entrenched by this time Lehmann’s market move in 1969 eventually proved successful and led to a resurgence in popularity for large-scale trains around the world.

Since then G Scale (or more accurately G Gauge) has become the standard designation for all large scale trains using 2-rail Gauge 1 track. However, it is a broad church embracing a range of differing scales including 1:13.7, 1:20, 1:20.3, 1:22.5, 1:24, 1:29 and even the original 1:32. This can be extremely confusing for newcomers who may be used to the smaller scales where there is far more consistency in scale.

G Scale is, therefore, something of a misnomer as the actual scale of the trains that run on it varies from system to system, and country to country.  G Scale should more correctly be called "G Gauge", as the gauge of the track (i.e. the distance between the rails) is the one consistency whereas G Gauge is a broad generic term that encompasses a wide variety of differing scales. Thus the track is always 45mm wide whereas the scales can change depending on the prototype railroad gauge that you intend to replicate.

The terms 'G Scale' and 'G Gauge' have largely become interchangeable which only adds to the general confusion.

Most of today’s large scale trains are far too big for indoor operations (although some enthusiasts are able to run at least part of their layout indoors) and are far more at home in the garden where there is much more room to build your railroad empire.

Despite the inclement British weather outdoor railways have grown immensely in popularity here as well as in the US and it is for this reason that the majority of G gauge track, trains and accessories are built to withstand the elements with many being both highly durable,  stabilised to UV rays and certainly water-resistant if not waterproof. Their large size and robust construction makes them relatively easy to handle and observe from a distance. G Gauge is used extensively in the USA to reflect standard gauge operations but is equally appealing for mining, logging and other narrow gauge roads (where LGB proved so popular).

LGB (the brand name introduced by Ernst Paul Lehmann Patentwerk which stands for “Lehmann Grosse Bahn” or “Lehmann Big Train”) are generally regarded as the founder of G Scale and became the largest European manufacturer of G Scale trains producing models of European and US outline, covering steam, diesel and electric prototypes as well as a large range of coaches, wagons, track and accessories.  The company cleverly exploited the existing 45mm gauge track already used in 1:32 mm scale and popularised it as 1:22.5 scale Narrow Gauge.

In recent years they have been beset by financial troubles and were saved from bankruptcy in 2007 by Marklin, another well know German model railway manufacturer. In 2009 Marklin themselves got into financial difficulty but have now emerged from insolvency and have resumed business under new management so hopefully the LGB brand is preserved.