Public holidays in Rhodesia weekend". Shangani Day was replaced as a public holiday by Occupation Day in 1920, but continued to be unofficially marked thereafter. Occupation Day, held on 12 September each year, marked the anniversary of the arrival of the Pioneer Column at Fort Salisbury in 1890, and their raising of the Union Jack on the kopje overlooking the site. It was renamed Pioneers' Day in 1961. Southern Rhodesia effectively became the entirety of Rhodesia in 1964 when Northern Rhodesia became independent as Zambia. After Southern Rhodesia's colonial government unilaterally declared independence from Britain on 11 November 1965, the anniversary became celebrated as
Northern Rhodesia for self-determination in 1922, this objection ceased, and in 1927 the Conservative Colonial Secretary, Leo Amery gave Southern Rhodesia settlers the impression that he supported their claim to acquire the more productive parts of Northern Rhodesia. At the end of the First World War, the European population of Northern Rhodesia was tiny, about 3,000 compared with ten times as many in Southern Rhodesia, but it increased rapidly after the discovery of the Copperbelt in the 1920s. Northern Rhodesian settlers wanted self-government for the European minority electorate, separate from Southern Rhodesia. However, once the British government appeared to reject the idea