Louis Brandeis, Chase National Bank v. City of Norwalk…
“ For in every case where a mortgage was given before the litigation against the mortgagor was instituted, the mortgagee is entitled to have a decision determining his rights rendered on the basis of the facts and considerations adduced by him. Obviously, the facts and considerations affecting the trustee's rights may be different from those presented to the state court on behalf of the Power Company. Because there is diversity of citizenship, the trustee under the mortgage is entitled to have the adjudication of his alleged rights made in the federal court. ”
