Stollwerck has been a German chocolate manufacturer since 1839, when it was founded by Franz Stollwerck in Cologne.
Franz Stollwerck was actually a baker. I do not know why he started to make chocolate, but he started out making hard candy, with a medicinal bias, and did particularly well with cough drops and lozenges. This was not greeted with kindness by local pharmacists, who protested, and even took it before the local council so that he would be made to stop, but he was not.
Then, in the 1860s, he started to not only bake cakes, but sell chocolate and marzipan. As chocolate and marzipan are often associated with cakes, perhaps the truth is that at one time he had too much filling and covering, and so he sold it, and people liked it, and so he made extra again. He also, by this time, ran a couple of coffee houses, perhaps why he started to make the cake. In any event he soon started to specialise in the sweets and the chocolate, and also opened bigger manufacturing premises. One of these was briefly converted into a music hall before becoming a chocolate and candy factory in the 1860s.
Franz Stollwerck died in 1876, and his five sons took over the business. Under their leadership the company expanded rapidly, into other countries as well. And they turned to technology, producing the first ever chocolate vending machines in 1887, from which you could extract a small sample of their product.
This then expanded to a network of machines from which larger bars of chocolate were sold; not just chocolates, too, they also had machines, especially at railway stations, for cigarettes, and soap (though hopefully not together), and, most intriguingly, for the sale of railway tickets.
Now the text on this card is primarily a history of polo, and it tells us that it is the oldest sport of all, two thousand years old, being first played in Persia. From the Orient it travelled to England and thence to other lands. It adds that polo is a sport for good riders. and good horses, though it also stresses that they are not strictly horses, but little ponies. It also gives us the dimensions of the field, 230 metres from end to end and seven metres as the span of the goal posts. This is not so far off today, when the playing area is 274 metres long and the goal posts 7.3 metres apart - the difference in the field dimensions being caused by the fact that there are now additional safety areas to protect the spectators, nine metres at each side and almost twenty-eight metres at top and bottom behind the goals.
The fronts of the cards that make up this group of six can be seen in full colour at Pre-War Cards/Stollwerck566. Looking at them it is plain to see that there are three sub-sets, golf, tennis, and horse sports, and that each pair consists of men and of women.
The female rider seems to be an odd woman out though, as it is not apparently clear which branch of equestrianism she represents. She is on a background with no other riders, but which could easily have shown a huntsman at full cry, or some hounds, and if she were doing dressage she would be dressed in a black habit, not a grey one. It appears that she is simply hacking, or enjoying riding in open country, but that would again be an anachronism because all the other cards show competitive sport.