The aim of this thesis is to study the presentation and subsequent application of the comprehensiveness of Islam in the Sudanese Islamic state under the leadership of Hasan al-Turabi from the year 1989 until 1999. Several studies have analyzed the history of the Sudanese Islamic state, however, the originality of the current study is in utilizing the concept of the comprehensiveness of Islam as the theoretical lens to review the history of al-Turabi's Islamic state. The current study has used two different sets of research methods. Firstly, for an in-depth investigation of how the concept of the comprehensiveness of Islam was understood and presented in al-Turabi Islamic state, several relevant al-Turabi books were analyzed. The aim of this analysis was to study the comprehension and presentation of comprehensiveness of Islam concept by the al-Turabi -the head of the Sudanese Islamic state. Thereafter, a historical analysis was conducted in order to analyze the practical application of the comprehensiveness of Islam concept by the Hasan al-Turabi’s. The study results have shown that the comprehensiveness of Islam was understood by al-Turabi as a basic part of the Islamic message. Moreover, the Sudanese theologian has underlined that the comprehensiveness of Islam is an indication of the truthfulness of the Islamic message. The second part of the analysis illustrated the practical application of the comprehensiveness of Islam through three main projects enforced by al-Turabi’s regime. These projects were: A) the implementation of the sharia laws in Sudan; B) a large project of Islamisation and Arabisation of the Sudanese society; and C) the creation of the Popular Arab and Islamic Congress (PAIC) as an international front towards a global spread of Islam.