An analytical method of solution to the non-linear problem of centrifugally generated free convection in a rotating porous box is presented. The free convection results from differential heating of the horizontal walls leading to temperature gradients perpendicular to the centrifugal body force. The validity of the solution was found to be restricted to small values of the centrifugal Rayleigh number, although this restriction was not explicitly imposed. The results are compared to an asymptotic solution of the corresponding problem for a long rotating porous box. A direct extraction and substitution of the dependent variables was found to be useful in this case for de-coupling the non-linear partial differential equations, resulting in a set of independent non-linear ordinary differential equations which was solved analytically. The solution results, their significance and their validity domain are discussed in their physical context.