When Frank Hornby first marketed his Mechanics Made Easy the forerunner of Meccano most of the models in the first book where railway oriented. It was therefore not too much of a surprise to see him branch out into model railways.

By 1914 two things where starting to come together. The first was that Meccano Ltd was now an established company, the second was that model railways where becoming increasingly popular. Scales had been established in the 1890s by the Marklin company, by 1914 the most popular was O gauge at 7mm to a foot, by modern standards quite large but ideal to take the clockwork and early electric motors of the time.

In 1915 Frank Hornby exhibited a tinplate train however he had to wait until after World War 1before he could market it. The First Hornby train set appeared in 1920, consisting of a simple 0-4-0 clockwork loco and tender, a single truck and an issue oval of track. The original train was held together with nuts and bolts, the track also though coming ready assembled it could be taken to bits, in effect an extension of the meccano system.

At the same time a tinplate set was marketed this was cheaper to produce than the one is with nuts and bolts, and allowed extra detailing. It as airly obvious which way this was going to go. Altough the bolted locos had the advantage of being able to take to bits and replace parts, the tinplate was more detailed and cheaper to produce. However the bolted construction method did continue with new sets 1 and 2

The models where decked out in the colours of 3 of the railway companies at the time, te LNWR, the same Midland and the Great Northern, with the Caledonion being added shortly after. The No 2 set had a larger 4-4-0 locomotive. Trackwork was also improved with more sleepers and clips to hold the track together.

New items quickly followed ranging from coaches and wagons to a footbridge the first trackside accessory.

1925 saw the advent of the first Electric powered loco. Ths was an electric loco from the Metropolitan Line an interesting choice, the loco was powered by a third rail which was partially realistic as many electric full size locos operted on a third rail.

1926 saw the second Electric set, followed by a number of new locomotives including for the first time locos in GWR green. However new Clockwork sets and locos continued to be produced as well.

The Hornby Blue train set produced in the 1926 was a step across the channel being a French train that was well known at the time in Britain.

More was to follow with 4-4-2 locos of the 4 groups as the railway companies had at the time become, the GWR, LMS, LNER and SR, however these where named after the trains at the time such as the Flying Scotsman which had a different wheel arrangement. However by 1929 these anomalies where stopped with the introduction of the No 2 specials the first locomotive that could be considered as a true model. Instead of making one basic loco and painting it in the colours of the companies Hornby started to make individual locos for each company a big step forward.

The 1930s saw further items coming onto the market , a very popular 0-4-0 tank along with the more accessories including passengers, posters and tunnels. Electricity was becoming increasingly common resulting in Hornby making electric versions of their older clockwork locos along with new locos.

The 1930's was the golden age for O Gauge, however things never stay the same. Electric was now very well established but technology moves on, electric motors where getting smaller meaning that smaller scale models could now be made, leaing to the introduction of Dublo. The other factor was that the 1930's ended in World War II. Hornby O Gauge world leave the 1930's on a high with the 4-6-2 Princess Elizabeth possibly the best O Gauge loco Hornby made.

During World War ll most of the Binns Road factory was given over to war work meaning that no new products would be launched.

Following the war O Gauge production recommenced however it would not be to the prewar volume, dublo was now the main scale of British model railways, Hornby O gauge continued through the 1950's but ended in the early 1960's, likely production ceasing in 1962 but supplies continued up until the Triang take over in 1964