Northern Rhodesia had been detained without trial, following claims that they had planned the indiscriminate killing of Europeans and Asians, and of African opponents, the so-called "murder plot". Shortly afterwards, on 12 March 1959, the governor of Northern Rhodesia also declared a State of emergency there, arrested 45 Zambia African National Congress including Kaunda and banned the party. Kaunda later received a 19-month prison sentence for conspiracy, although no credible evidence of conspiracy was produced. The declaration of States of emergency in both Northern Rhodesia and Nyasaland marked the end of attempts by their nationalist parties to work within the colonial system,
Northern Rhodesia local rulers and British legislation gave it the status of a protectorate. The territory attracted a relatively small number of European settlers, but from the time these first secured political representation, they agitated for white minority rule, either as a separate entity or associated with Southern Rhodesia and possibly Nyasaland. The mineral wealth of Northern Rhodesia made full amalgamation attractive to Southern Rhodesian politicians, but the British Government preferred a looser association to include Nyasaland. This was intended to protect Africans in Northern Rhodesia and Nyasaland from discriminatory Southern Rhodesian laws. The Federation of Rhodesia and Nyasaland formed in 1953