Roman Catholics and Protestants in Ireland

The original conflict between the Catholics and Protestants in Ireland was not truly a matter of religion -- it was a matter of social class.

Put quite briefly, the majority of the population in Ireland, post 1000 A. D., was Catholic. They never underwent the church reform that England did in the 1500s. Thus, by the 1600s, England = Anglican (Protestant), and Ireland = Catholic.

When England began to establish plantations in Ireland and establish themselves as the ruling class, they often did it in a relatively unpleasant and domineering fashion, making themselves unpopular with their new subjects in the manner of America and India.

Hostility arouse between Catholics and Protestants in this way not because the religions themselves bore marked differences, but because these denominations were attached to two very different classes. Intermarriages were frowned upon, not for spiritual reasons, but because the Protestant was marrying below their class.

This hostility between the denominations continued into the present for many of the same reasons. Protestantism represents the continued presence of England in Northern Irish affairs, while Catholicism bears the stigma of being the religion of the poor, the rebels, and the socialists intent on a free Ireland.

I hope this helps answer your question. Tim Pat Coogan has published some very good books on the subject, and many books on the IRA give good, concise histories of earlier conflicts before the IRA.