In the first four years following Nigeria's return to democratic rule in 1999, at least 10,000 people were killed in communal violence across the country, but in recent years, these clashes have been notably less frequent.
By Dan Isaacs
Former Nigeria correspondent
But this latest unrest in Plateau State is a worrying indication that these tensions remain never far from the surface, and that, in a country with such high levels of poverty, the underlying issues of access to scarce resources such as land and jobs are as much of an issue as ever.
Several hundred people are reported to have been killed in Jos
Some of the violence has pitched Muslims against Christians, but all of them have fallen across different tribal and cultural divides.
From the deserts of the north to the tropical forest regions of the south and east, it is home to around 120 million people, divided up into some 250 different ethnic groups.
The broad characterisation of a Muslim Hausa-speaking north, and a Christian south made up of two dominant tribes - the Yoruba in the south-west and the Ibo in the south-east - is a vast over-simplification.
In some states across central Nigeria, for example, it is possible to drive down a road, stopping at each tiny settlement, encountering a different language spoken in every single one.
And to further complicate this ethnic mix, over the decades and even centuries, people have moved around what is now modern day Nigeria.
A substantial minority of southern Christians now live in the north, as many northern Hausa Muslims have migrated south.
So, conflict between these communities, when it does occur, is a complex affair.
It can be rooted in religious disagreements - the introduction of Islamic law, for example, in some northern states has proved extremely contentious.
Whatever the historical justifications, the conflict is always and everywhere about access to scarce resources
But it most often boils down to competition between those that see themselves as the true 'indigens' of an area, and those that are considered to be more recent 'settlers'.
Whatever the historical justifications, the conflict is always and everywhere about access to scarce resources.
This might be farmland, or employment, or access to political power. It could even be jealousy over the provision of water or electricity to one village but not its neighbour.
At their root, these differences are not cultural or religious. They are economic.
The tragedy of Nigeria is that over the past few decades its population has grown rapidly, but despite the country's vast oil wealth, the economy has failed to keep pace.
Nigerians have been getting poorer by the year.
And along with this, the failure of the state to provide adequate education for the vast majority of the population, has produced a frustrated and angry underclass of largely urban, unemployed youths.
It is to this disempowered group that ambitious politicians and religious leaders look for support.
Sometimes it is for the best of motives - to find ways to improve their lot in life by representing their interests.
But more often, the motive is personal ambition.
A politician without a power base is worthless. A politician with an army of supporters behind him can win elections and influence people.
Many observers in Nigeria believe that the roots of the violence across much of the country are not religious or cultural.
They say the conflicts are created and stoked by politicians both at a local and national level who seek to gain advantage from social division.
It is a cynical view, but one that has strong evidence to support it.
Shops, houses, churches and mosques were burnt in Jos
One need look no further than means used to distribute the country's vast oil wealth from the federal government in Abuja to the local level.
It all travels down this path in the form of contracts handed out to political favourites.
Contracts for building roads, schools, and hospitals; for supplying electricity, water and medicines.
In fact, almost all economic activity in the country works on this principle - the awarding of contracts. It makes those with access to the source of power rich, and those who do not have power want it all the more.
And caught in the middle of all this are the ordinary Nigerians, whose local disputes are hijacked by cynical politicians prepared to pay sections of the community sums of money to foment unrest.
And that's all it takes.
Once triggered, the violence has its own momentum.
Muslims hear that Muslims are being killed elsewhere and take up arms to kills Christians in their own neighbourhood.
And then, perhaps, Christians in another part of the country will get to hear about their brothers being murdered and carry out reprisals on local Muslims.
It is a cycle that is difficult to break, particularly if it is repeatedly nudged over the edge by the politicians, or even external influences.
Take for example, the riots in the northern city of Kano in October 2001.
That began after a peaceful anti-US demonstration by local Muslims, angry at the bombing of Afghanistan.
It quickly degenerated however into a violent inter-faith battle, most probably stoked up by local political rivalries.
The cause, therefore, was not religious, but because the riots pitted Muslim against Christian, they had the appearance of being so.
This article was first published in 2002.