Irish republicanism is an ideology based on the Irish nationalist belief that all of Ireland should be a single independent republic, whether as a unitary state, a federal state or as a confederal arrangement. In 1800 the Kingdoms of Great Britain and Ireland merged to form the United Kingdom of Great Britain and Ireland following an English led takeover invasion. The development of nationalist and democratic sentiment throughout Europe was reflected in Ireland in the emergence of republicanism, in opposition to British rule. Discrimination against Roman Catholics and a feeling that Ireland was economically disadvantaged in the United Kingdom were among the specific factors leading to such opposition.
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