During the 1920's there was a new president named Arturo Alessandri Palma, he was popular in his decisions earning the nickname "Lion of Tarapaca". Though he had problems when he commited the similar action to that of Balmaceda when he bypassed the legislators in 1924.
Military Coup
Alessandri's power was removed in 1924 when there was a double military coup, much chaos followed until 1932 an upsetting example of this is the Marusia massacre leading to many miners and their families being killed. More social unrest followed with the Seguro Obrero Massacre in 1938 with youth of the national socialist movement being lined up and killed after a shootout.
The liberals radical party was then in power from 1932 until 1952, in the 1970 election Salvador Allende Gossens won overall power and his initial time in charge went well with the economy having a significant boost. Though an economic depression wasn't far behind and things took turn for the worst.
Augusto Pinochet
In 1973 the military staged an attack on the presidential palace to which Allende controversially committed suicide allowing the leader of the military Augusto Pinochet to take charge. It was another dark patch in the history of Chile where the economy was a mess and people were being tortured and killed on a vast scale.