Dairy Queen, Inc. (DQ) (defendant) signed a licensing contract with McCullough (plaintiff), a partnership that owned the trademark "DAIRY QUEEN." Pursuant to the contract, DQ agreed to pay McCullough $150,000 for the exclusive right to use the trademark in certain portions of Pennsylvania. When DQ defaulted on its payments, McCullough sent DQ a notice of termination letter cancelling DQ's right to use the trademark. However, DQ continued to use the trademark after the notice. McCullough brought suit for breach of contract. McCullough sought, among other things, "an accounting to determine the exact amount of money owing by [DQ] and a judgment for that amount." In its answer to the complaint, DQ demanded a trial by jury. McCullough filed a motion to strike that demand. The United States District Court for the Eastern District of Pennsylvania (Wood, J.) granted McCullough's motion, finding that the action was "purely equitable" because the complaint framed the action in terms of an "accounting" rather than for debt or damages. DQ sought mandamus in the United States Court of Appeals for the Third Circuit to compel Judge Wood to vacate the order granting McCullough's motion to strike. The Third Circuit denied DQ's petition. The United States Supreme Court granted certiorari.