Powder keg

In practical use, powder kegs were small casks to limit damage from accidental explosions.

A powder keg is also a metaphor for a region that political, socioeconomic, historical or other circumstances have made prone to outbursts.

The analogy is drawn from a perception that certain territories may seem peaceful and dormant until another event triggers a large outburst of violence.

[2] The term is most often used to simplify and help the understanding of what is often a complex set of circumstances that lead to conflicts, such as the powder keg of Europe.

The most cited event attributed to the use of the term was the assassination of Archduke Franz Ferdinand in Sarajevo, Condominium of Bosnia and Herzegovina in 1914, the immediate trigger of World War I.