Custer's image and his exploits became iconic in the decades following his death. For instance, in the 1890s the Anheuser Busch brewery began issuing color prints titled "Custer's Last Fight" to saloons across America. The prints were generally framed and hung behind the bar, and were thus seen by millions of Americans.
This particular illustration comes from another bit of vintage pop culture, the cigarette card, which were small cards issued with packs of cigarettes (much like the bubblegum cards of today). This particular card portrays Custer attacking an Indian village in the snow, and thus appears to depict the Battle of the Washita in November 1868. In that engagement, Custer and his men attacked a Cheyenne camp on a frigid morning, catching the Indians by surprise.
The bloodshed at the Washita has always been controversial, with some critics of Custer terming it little more than a massacre, as women and children were among those killed by the cavalry. But in the decades following Custer's death, even a portrayal of the Washita bloodshed, complete with women and children scattering, must have somehow seemed glorious.