The Islamic State may have lost its self-styled caliphate, but its barbaric back catalogue of grisly execution videos will continue to haunt the global imagination and serve as a template for how to sow terror, analysts say.

The 1990s break-up of Yugoslavia unleashed a series of bitter wars marked by atrocities, genocide and massacres that left more than 130,000 people dead.

Bloody assaults at two New Zealand mosques that left at least 40 people dead are the latest in a series of attacks on civilians by extremists around the world.

Here is a rundown of some of the most serious since 2015.  

As final defeat looms, militants of the Islamic State group have remained organized and ruthless to their last breath. Keeping institutions functioning in their last shred of territory, they are continuing benefits like food and money to supporters while their religious police and fighters still impose their rule of fear and brutality.

Refusing to surrender, the militants have tried to squeeze out any last possible gain. Over the past three weeks, they secured the evacuation of more than 10,000 of their exhausted and wounded followers, looking to ensure long-term survival and continued conflict.

A string of violent escalations have pushed India and Pakistan to the brink of conflict, sparking global alarm and calls for restraint between the nuclear-armed neighbours.

India and Pakistan have fought two wars and countless skirmishes over Kashmir, the Himalayan region claimed in full by both nuclear-armed rivals.

Palestinian residents of Kufr Aqab, just north of Jerusalem, could be forgiven for thinking they live under two governments at once, or perhaps none at all. 

Opposition chief Juan Guaido stunned the world on January 23 when he declared himself acting president of Venezuela, plunging the crisis-hit country into new turmoil.

When you want results in a polarized Washington, sometimes it pays to simply leave the professionals alone to do their jobs.

That seems to especially be the case now in an era in which liberal House Democrats are sharing power in Washington with a GOP-led Senate and President Donald Trump.

The United States led the Western intervention in Afghanistan 17 years ago to rid Al-Qaeda of its sanctuaries following the 9/11 terror attacks.