Abstract
Democracy is a system in which the citizens are endowed with a set of inalienable rights, and hold the sovereignty of the power. A parliamentary democracy is a political system in which the citizens allow their representatives, the members of the parliaments to act in their name and place through an electoral process. The Great Britain's parliamentary system is that of bicameralism. The British Parliament is divided into two Houses. The first one is the House of Commons composed of 651 directly elected MPs and the House of Lords with hereditary nobles, bishops, judges and life peers nominated by the major political parties that are entitled to sit and debate on significant issues. The legitimacy conferred to the House of Commons makes it the most important and powerful one. In general parlance, the British parliament means the House of Commons. The separation of powers theorized by the French social commentator Montesquieu requires to separate the executive power from the legislative. However, Great Britain has the particularity not to have a written constitution establishing clearly the roles of each institution in the political system. Nevertheless, a system of checks has been set to ensure the balance of power. In this document, we examine the various political, administrative and economic changes undergone by Britain that affected its Parliament over the 20th century.
