The first event was held as an invitational tournament, but the next year Prestwick Golf Club declared that "the belt... on all future occasions, shall be open to all the world". In its early years it was often referred to as The Championship but with the advent of the Amateur Championship in 1885, it became more common to refer to it as The Open Championship or simply The Open. The tournament inspired other national bodies to introduce open golf tournaments of their own, such as the U.S. Open, and later many others. To distinguish it from their own national open, it became common in many countries to refer to the tournament as the "British Open". The R&A (the tournament's organiser) continued to refer to it as The Open Championship. During the interwar years, a period with many U.S.-based winners, the term British Open would occasionally be used during the trophy presentation and in British newspapers.