Ah! So I was mistaken in my first analysis, it was only showing me the first texture i'd loaded! Thanks mhagain, your response led me to the function D3D11CalcSubresource, which in turn led me to realize that the problem wasn't in the portion of my code where I mapped, memcpy'd, and unmapped (after I updated it per your response of specifying the subresource). It was in the portion after, where I created the shader resource view and copied my texture set up as D3D11_USAGE_STAGING to one set up as D3D11_USAGE_DEFAULT. I was only copying the first subresource.