A constitutional monarchy is a form of monarchy in which a ruler is forced to abide by written laws, legislatures, and/or customs, setting it apart from an absolute monarchy. Constitutional monarchies typically consisted of a ruler, a Prime Minister, and a Parliament, with the ruler either appointing parliament members or the people (typically "landed" voters) electing officials to represent them. The purpose of a constitutional monarchy was to ensure that tyranny would not govern the people of a country, and that rulers would be forced to acknowledge the views of their subjects. By the 21st century, most "constitutional monarchies" were pretty much republics with monarchs as their figureheads. The United Kingdom was the first major constitutional monarchy in Europe, adopting the Magna Carta as its constitution in 1215, and most absolute monarchies were forced to adopt constitutions during the 19th century.