By the 1830s, the Westminster system of government (or cabinet government) had emerged; the prime minister had become "primus inter pares" or the first among equals in the Cabinet and the head of government in the United Kingdom. The political position of prime minister was enhanced by the development of modern political parties, the introduction of mass communication and photography. By the start of the 20th century the modern premiership had emerged; the office had become the pre-eminent position in the constitutional hierarchy vis-à-vis the Sovereign, Parliament and Cabinet.