The Stanley Cup is the championship trophy awarded annually to the National Hockey League (NHL) playoff winner. It is the oldest existing trophy to be awarded to a professional sports franchise, and the International Ice Hockey Federation (IIHF) considers it to be one of the "most important championships available to the sport". Originally commissioned in 1892 as the Dominion Hockey Challenge Cup, the trophy is named after Lord Stanley of Preston, then–Governor General of Canada, who donated it as an award to Canada's top-ranking amateur ice hockey club, which the entire Stanley family supported, with the sons and daughters playing and promoting the game. The first Cup was awarded in 1893 to Montreal HC, and subsequent winners from 1893 to 1914 were determined by challenge games and league play. Professional teams first became eligible to challenge for the Stanley Cup in 1906. In 1915, the two professional ice hockey organizations, the National Hockey Association (NHA) and the Pacific Coast Hockey Association (PCHA), reached a gentlemen's agreement in which their respective champions would face each other annually for the Stanley Cup. After a series of league mergers and folds, it was established as the de facto championship trophy of the NHL in 1926 and then the de jure NHL championship prize in 1947.