The Second Italo-Abyssinian War (also referred to as the Second Italo–Ethiopian War) is a brief war, begun in October 1935, between the Kingdom of Italy and the Ethiopian Empire (also called Abyssinia).

The war is infamous for the Italian illegal use of mustard gas.

The war result in the annexation of Ethiopia into Italian East Africa.Politically, the war is best remembered for exposing the inherent weakness of the League of Nations.

The Abyssinia Crisis, along with the Mukden Incident (the Japanese annexation of three Chinese provinces), is often seen as a clear example of the ineffectiveness of the League.

Both Italy and Ethiopia are member nations; the League is unable to control Italy or to protect Ethiopia.