I believe that Viking deserve a place of honour amongst British Classic Factory Lightweights. They really got going in the late 1940s with a good range of bicycles and team sponsorship and racing success right through until the mid 1960s when the decline in club cycling and recession expedited their demise.
It is hard to analyse the company’s strengths and weaknesses from this distance, but I imagine that they always had an uphill struggle with the peculiar cycling club scene in the UK. In mainland Europe, the world centre of cycle racing, manufacturers designed and built good standard racing bicycles which people bought and raced. In the British backwater, there was more emphasis on the bespoke: riders wanted to specify their tubes and their lugs and their angles and their dropouts and their brazed-on fittings. And their local shop would oblige. There were of course some excellent craftsmen, and some mediocre ones, and some jobbing builders who would build frames for any local shop to slap their name on.
I am sure that Viking would have liked to build a standard product for the sake of efficiency and, on the face of it they did, but the customer could actually specify almost any variation they wanted, and pick from a wide range of colours too. A typical example would be the 1955 Viking Severn Valley on this site that was built to order. The frame had at least 4 deviations from standard specification and probably all the components except the seat post were either non-standard or selected from a range of options. A Continental European manufacturer would doubtless have offered this model with one specification and perhaps the choice of a few colours. On the other hand, it may be that Viking could not have sold many high-range bikes if they didn’t strive to give the customer the same sort of choice that they would get from a custom builder.
For more on Viking, go to http://classicvikingcycles.uk