The Act of Catholic Emancipation was a law passed in the United Kingdom in 1829. It allowed Catholics to sit in Parliament and hold public office, which had been restricted for over a century. This act was a significant step towards religious equality in Britain, as it removed many legal barriers that discriminated against Catholics. The movement for Catholic emancipation gained momentum through the efforts of leaders like Daniel O'Connell, who campaigned tirelessly for the rights of Catholics. The act was a response to growing public support for reform and helped to alleviate tensions between different religious groups in the country.