There is nothing inevitable about the expansion of democracy. Among countries with populations above one million, there were only 11 democracies in 1900, 20 in 1920 and 29 in 1974. Only for the past quarter of a century has democracy been the world’s predominant form of government. By 1993, the number of democracies had exploded to 77—representing, for the first time in history, a majority of countries with at least one million people. By 2006, the number of democracies had ticked up to 86.
The Global Crisis of Democracy
As China and Russia attack free governments and push strongman rule, the U.S. has gone silent—and a new tide of authoritarianism is gathering.
by Larry Diamond
That makes it – 6
Presidential System of Democracy
Mexico (1917) (Thanks to @World Engineer)
UK (1688) (I am not sure of its inclusion, because if this is included then a significant region of western Europe may also be included so also Australia and New Zealand, which will take the number way beyond 11)
Canada (1867) Independence through British North American Act 1867.