It appears to me that ever since couples had kids they at the same time had the trouble of putting them to bed in the evenings. I believe all cultures have their "strategies" to finally get their offspring to sleep. Many would read bedtime stories or fairytales to them, before or after that they say a prayer with them, and then hope they fall sleepy and end up dozing away.
This activity has long a tradition in all cultures, and it is reasonable that stories and fairytales were passed on and inherited as well as they were written down, like by E.T.A. Hoffmann or Hans Christian Andersen. Stories that calm the excitement of our kids, that create an atmosphere of peace and safety and that give rest and comfort.
Some of these stories also cover our every morning's experiences: We all well know that upon rubbing one's eyes after wake up some sandy grains must have been put to them over night. Who could have done such? And for what reason? As we have no idea how those came to be there, the character of the Sandman was invented and made responsible for this. The sand man. A little gentle and harmless man who by dusting sand to our eyes gradually closes them, puts us to sleep and cares for warm dreams. This at least is what Germans think and it is a known tale in Europe. Further I assume that even in the States such story is known as the song comes to my mind: "Mr. Sandman, bring me a dream."
Yet I also believe that the sandmen all over the world differ much. I can even think of a sand-woman, a sand-fairy, a sandstorm even or a dwarf or wizard. As long as it explains how come we dream and how come we find those sandy grains in our eyes every morning.
Now here in Germany we even had an East German Sandman and a West German Sandman. The Berlin television company Sender Freies Berlin (SFB) was about to come up with a Good Night TV short story program for kids when the East German TV company Deutscher Fernsehfunk (DFF) found out about that and entered into competing to be the first to go online with such a TV programme. And indeed the DFF broadcasted the first Sandman TV short-story for kids on November 22 in 1959 while SFB did so only on December 1 that the same year. The German Democratic Republic (GDR) sandman was a little white haired man with a round face and friendly eyes, a white beard and red coat and cap. In the end of every story he would dust a hand full of sand into the kids' eyes and then friendly wave his hand for a good night greeting. In the Federal Republic of Germany (FDR) there were rather changing characters in the good-night-stories and the sandman came gently flying on a cloud.