Question

Creation of a party within a government:
National Socialist Party 1919
The Social Democratic Party

Using Economics to gain support:
New Economic Policy 1921
Employment Miracle: 1939

Revolutions:
Munich Beer Hall Putsch (1923)
1917 Revolutions (April, July, September, October)

Using weakness of previous government:
Weimar Republic after 1929 Wall street crash
Provisional Government's weakness in authority