In the last few weeks, several hundred have died, and over 50,000 fled their homes because of tribal violence. Nigeria has some 250 ethnic groups (many organized as tribes around shared customs, language and culture) in a population of 122 million. Many consider it a miracle that the nation survives at all. Without the century long colonial period  (mid 19th to mid 20th century), Nigeria would not exist at all. Instead, it would be a collection of several dozen kingdoms, organized around the largest and most cohesive tribes. Warfare, as was the case in the pre-colonial period, would be constant. Each of the kingdoms would have ethnic minorities that would either be rebellious, or urged to go that way by ethnically related people in neighboring kingdoms. The one sub-Saharan nation that was not colonized, Ethiopia, experiences frequent civil war and rebellion because of its dozen or so different ethnic groups. No one has yet come up with a quick solution for this problem, for the problem itself is unique. Historically, the only thing that works is gradual absorption of many of the smaller groups into the larger ones. This has been going on more rapidly in the last few centuries, making it easier for many stable nations to form. Africans want to hold on to their colonial era borders, even if it means constant threat of unrest. This is preferable to the pre-colonial tribal warfare.  But the current violence is a classic example of how difficult it is to keep the peace. The Tiv people speak a language that can be traced to areas to the south of Nigeria. They have apparently been moving into Nigeria over the past few centuries. The local Hausa tribes regard the Tiv as unwelcome interlopers and it never took much to spark a bloody confrontation over the issue.