12 December 1963
Kenya gained its independence from Britain with Jomo Kenyatta as the country’s first Prime Minister. The Union Jack was replaced by the black, red and green flag of the new nation. This followed the first all inclusive elections on 27 May 1963. A year later Kenya was declared a Republic. The campaign for independence in Kenya dates back to the 1940s before Kenyatta became the leader of the Kenya African Union (KAU) in 1947 and birth of the Mau Mau rebel movement. In 1952 in response to the Mau Mau rebellion, the government declared a state of emergency which lasted for eight years. During the state of emergency a number of Mau Mau operatives, including Kenyatta and Achieng Aneko were arrested. In 1953, Kenyatta was charged with leading the Mau Mau rebellion and sentenced to seven years in prison. When Kenya became a Republic on 12 December 1964, Kenyatta was named Kenya's first president, with Jaramogi Oginga Odinga as his vice-president.
References

The New York Times,"Kenya Gains Independence",From: The New York Times,Available at:learning.blogs.nytimes.com [Accessed : 25 November 2013]