If the peeling is occurring all across the wood surface, then there is a problem with the paint combinations that you used, or the wood was not primed properly. The result is that the paint is not adhering well. If the peeling is on specific areas of the surface, then it is most likely a moisture problem. Verify that flashings and poor caulking are not letting rainwater behind the paint. Modern insulation has also changed this house. The insulation holds the heat and the siding freezes much more than it did in 1815. If, however, a house is not sealed completely, or at least as well as possible, humidity will escape, and painted areas where the humidity escapes and freezes are going to suffer damage. The obvious areas where humidity would escape would be around window edges, electrical outlets, and wall and floor joints. Examine the areas where the paint is peeling and see if it corresponds to an area inside that may be allowing humidity to pass. If it is an electrical outlet, install a gasket. If it is a window, then make sure the window edges are properly caulked from the inside.