Why did Italy declare war on Germany in WW2?

On this day in 1943, the government of Italy declares war on its former Axis partner Germany and joins the battle on the side of the Allies. ... World War II. 1943 ... read more

On this day in 1943, the government of Italy declares war on its former Axis partner Germany and joins the battle on the side of the Allies. read more

Below is a table showing the Outbreaks of Wars between Nations which occurred during World War II. Indicated are the dates (during the immediate build-up to, or during the course of, World War II), from which a de facto state of war existed between nations. read more

Assuming that the facts of September 1943 (Italy surrenders) are well known (judging from some answers I haven't this impression) let us come to why the Kingdom of Italy declared war to Germany. read more