LONDON (AP) — Europe in 2015 witnessed the greatest movement of people since World War II, as desperate refugees fleeing Middle East violence arrived by the hundreds of thousands on its shores. The continent also suffered extremist attacks that exposed the vulnerability of its civilians and challenged its way of life.

Africa suffered devastating attacks as well but also welcomed Pope Francis with joy.

As the tumultuous year draws to a close, The Associated Press is looking back on 12 months of upheaval in Europe and Africa by presenting the most memorable images by AP photographers. These stories highlight how interconnected the world has become, with Europe facing grave challenges stemming in large part from unrest in the Middle East.

Deadly attacks on Paris touched a global nerve — in January with the slaughter at the satirical newspaper Charlie Hebdo, and in November with coordinated attacks in Paris that claimed 130 lives and wounded hundreds. But there were major extremist attacks elsewhere as well — in Nigeria, Tunisia, Turkey and other countries.

Memorable —and often painful — images came from other tragedies, including a plane crash in the French Alps, a deadly fire in a Romanian nightclub and a political assassination in Moscow.

The migration crisis produced some of the most iconic images of the year along the hazardous journey toward northern Europe. Some refugees exulted in their survival, raising their arms in joy and relief when their flimsy rafts made landfall in Europe. Others drowned in the sea, including 3-year-old Aylan Kurdi, whose lifeless body was photographed after washing up on a Turkish beach and galvanized the world's horror at the unfolding crisis.

These photographs show a Europe that is both less isolated and more vulnerable, its borders elastic, its control mechanisms threatened, its capitals both defiant and fearful.