Northern Ireland has historically been divided along religious lines between its Protestant and Catholic populations. Centuries of English rule and settlement led to discrimination against Irish Catholics. While Ireland gained independence in 1921, Northern Ireland remained part of the UK. This led to sectarian conflict and violence throughout the 20th century as Catholics faced discrimination and demanded civil rights. Key events like Bloody Sunday exacerbated tensions and fueled support for paramilitary groups on both sides. Peace negotiations in the late 1990s led to the Good Friday Agreement and establishment of local government, but divisions remain between the two communities.