From the African bush to Indonesia’s shores, the number of wars worldwide has dropped to a new low, peace researchers report. But the face of conflict is changing, they say, and free-for-all violence in such places as the Congo can defy their definitions.

“To say conflict as a whole is in decline, I could not draw that conclusion,” said Caroline Holmqvist of Sweden’s Stockholm International Peace Research Institute.

That institute’s newly released Yearbook 2006, drawing from data maintained by Sweden’s Uppsala University, reports the number of active major armed conflicts worldwide stood at 17 in 2005, the lowest point in a steep slide from a high of 31 in 1991.

The Uppsala experts added one conflict to their list in 2005: the resurgent war between the 4-year-old Afghan government, with its U.S.-led allies, and fighters of the ousted Taliban. But they also subtracted three: conflicts that ended in Rwanda, southern Sudan and Algeria. Those joined such other recent additions to the “peace” column as Liberia and Indonesia’s Aceh province.

The deadliest war of 2005 was the complex conflict in Iraq, where latest estimates say a minimum of 50,000 people have been killed since the U.S.-British invasion of 2003. The oldest conflict, dating to 1948, is the separatist struggle of the Karen people in Myanmar.

The 14 other major armed conflicts listed by Uppsala University for 2005 were in Burundi, Uganda and Sudan’s Darfur province in Africa; in Colombia and Peru in Latin America; the global U.S. campaign against al-Qaida; in Turkey and in Israel and the Palestinian territories in the Middle East; in the Russian republic of Chechnya; two insurgencies in the Philippines; and in Sri Lanka, India’s Kashmir region and Nepal in Asia.

Nepal’s government and Maoist rebels appear since to have reached a peace accord, but new flareups in Somalia and elsewhere in 2006 may counterbalance such further gains for peace.

Stockholm’s Holmqvist noted that war between nations has become a rarity. “War as ‘a continuation of politics by other means’ has been delegitimized over the past 50 years,” she said. But she added that more undefinable kinds of conflict are making headlines these days, “with a decentralized, fragmentary nature, without identifiable political agendas, often with no apparent leader.”

She cited the example of the Democratic Republic of the Congo, where ethnic militias in the northeast have been “fighting each other in ways that are less easily defined or explained.” Holmqvist said even recent anti-police violence in Brazilian slums verges on the definition of armed political conflict.

A “major” armed conflict, by the Uppsala definition, is one that causes at least 1,000 battle-related deaths in a year.