We removed this drywall due to water damage.
Underneath was beadboard and old pink insulation. It was damp and smelled of mildew/ mold. There was no vapor barrier or house wrap, so water was seeping through the vinyl siding.
At some point there was a wall of windows(s) here. They were removed and replaced with this one window. The window frames were covered with wood planks, and the siding was nailed directly to the planks.
This old bead board was gently removed and is being stored for a future project.