Ethan returns to the family homestead.
This scene opens with shots of the characters riding horses with the landscape in full view, I believe this is shown to represent the availability of land in the American west, this relates to the myth that the frontier/American west was the edge of the settled country where unlimited free land was available to everyone.
This scene also portrays the native Americans as murderous and dangerous predators as they set the family home on fire, killing those who are inside also it is hinted toward the possibility that the Indians has raped Martha shown through Ethan picking up the dress before finding her body. As we are watching the film from the perspective of the settlers we view the native Americans as the villains of this story, which is a common theme in westerns and in old literature.
I believe this scene reinforces the myth of the American west by showing the Native Americans in such negative light and through the myth of the wild west which can be shown through the character of Ethan as he is shown as a stereotypical cowboy, for example his clothing and violent nature (when he punches the other character).