Twelve years after the previous Games, the 1948 Summer Olympics, in London, attracted competitors from 59 nations, including 14 that made their Olympic debut; once again, Germany was not invited to take part, and neither was Japan. The 1952 Games, in Helsinki, again set a new high, with 69 nations participating, including the first appearance by the Soviet Union and the return of Germany and Japan. The 1956 Summer Olympics, attended by 67 nations in Melbourne, were the first to be marred by a boycott. Egypt, Iraq, and Lebanon withdrew in response to the Suez Crisis, and the Netherlands, Spain, and Switzerland withdrew in response to the Soviet invasion of Hungary. Because of Australian quarantine restrictions, the equestrian events were held five months earlier in Stockholm, with a total of 29 participating nations, including five nations that did not compete in Melbourne.