History of Sudan
The modern Republic of Sudan was formed in 1956 and inherited its boundaries from Anglo-Egyptian Sudan, established in 1899. For times predating 1899, usage of the term "Sudan" for the territory of the Republic of Sudan was somewhat anachronistic, and may have referred to the more diffuse concept of the Sudan.
Sudan
The Egyptian revolution of 1952 finally heralded the beginning of the march towards Sudanese independence. Having abolished the monarchy in 1953, Egypt's new leaders, Mohammed Naguib, whose mother was Sudanese, and later Gamal Abdel Nasser, believed the only way to end British domination in Sudan was for Egypt to officially abandon its claims of sovereignty. In addition Nasser knew it would be difficult for Egypt to govern an impoverished Sudan after its independence. The British on the other hand continued their political and financial support for the Mahdist successor, Abd al-Rahman al-Mahdi, whom it was believed would resist Egyptian pressure for Sudanese independence. Rahman was capable of this, but his regime was plagued by political ineptitude, which garnered a colossal loss of support in northern and central Sudan. Both Egypt and Britain sensed a great instability fomenting, and thus opted to allow both Sudanese regions, north and south to have a free vote on whether they wished independence or a British withdrawal.