The inaugural season of the Campeonato de Portugal (Championship of Portugal) took place in 1921-22, and this competition was played every season until 1937-38. The original format had all the clubs participating in regional leagues, with the regional winners progressing to knock-out rounds, and the ultimate victors named Champions of Portugal. This was the primary tournament in Portugal, until the creation of the round-robin competition in 1934-35 - in fact, the Champions moniker of this early period can be misleading, as the modern concept of champion applies to the league champion (i.e., for statistical purposes, the winners of this Campeonato de Portugal are no longer counted among Portuguese League champions). The short period of coexistence between two championships meant considerable confusion, and was pointed as a reason for lack of competitiveness in contemporary international matches - therefore, a revamp was bound to happen.
The success of the older competition meant it was carried over after the reorganization of Football competitions in 1938-39, albeit losing its top status: the (round-robin) league carried the name Campeonato (or, in its longform, Campeonato Nacional da Primeira Divisão), and the old Campeonato de Portugal was renamed Taça de Portugal (Portuguese Cup) for the 1938–39 season. The Cup soon became the second-most important trophy in portuguese football.