When did Napoleon Bonaparte become king?

In 1799 he became the First Consul of the Executive Government of the First French Republic.
On 2 August 1802 a national referendum was held that gave him the title of First Consul for Life. He was no longer bound to a 10 year term of office. His reforms were in place and France prospered. His opposition from within the Army were sent to San Domingo to put down the slave revolt and the unhappy royalists were exiled when he exposed them for plotting against his leadership. On 18 May 1804 the Senate passed a Bill introducing the French Empire with Napoleon as Emperor.
On 2 December 1804 Napoleon Bonaparte crowned himself Emperor of the French.