Only a few countries, mainly in Europe, had central banks before the twentieth century.
Central banking did not became widespread in the Americas until the period between the
First and Second World Wars, and did not become widespread in Africa and Asia until
after the Second World War.
There were certain arrangements of monetary authorities alternative to central banks.
Among the other monetary systems that once were widespread were currency boards.
After decades of decline, currency boards have enjoyed a revival of interest in the 1990s.