The main aim of the study is to explore and identify the Omani political and cultural issues. It focuses on correcting the commonly mistaken ideas regarding the chronological sequences of the ancient Omani Imams at that time. It also refers to the intellectual and cultural movements accompanied by the glory of culture represented by the writings of Fiqh (Jurisprudence) encyclopedias. To achieve the aims, the researcher tends to gain knowledge via reading ancient written texts. The study includes three major parts: the introduction, the preface, three chapters and the conclusion. The first part discusses the political life in Oman from 401 Hijri (1010 AD) to 513 Hijri (1119 AD). It also talks about the situation of Oman at the beginning of the specified era. How Omani people could defeated the invaders is also pointed out in this part. According to authentic recourses, the researcher mentions the history of Imams and their biographies. The second part is about the intellectual remains of two important schools of thoughts: Nizwania and Rustaqia. These were founded after the decline and the disposition of Imam Assalt bir Malik AlKharoosi (273 Hijri / 886 AD). The third part deals with the cultural situations and how it enriched the General Fiqh Encyclopedias. The conclusion clarifies the most important results of the current research. These include the changes in the chronological sequences of the Imams during that period and how the two schools of thoughts developed the Omani culture. The main findings of this study are listed below: 1. Bani Makram who ruled Oman in the early 5th Hijri /11th AD century were originally not Omanis. 2. Imam Rashid bin saeed Alyahmadi was leader in fighting the Bwaihis of Bani Makram until he died as a martyr. 3. Imam Alkhaleel bin Shathan Alkharoosi was the second Imam of that period. 4. The Rustaqi and Nizwani schools of thoughts had vital roles in flourishing the improvement of the culture in Oman. 5. Unlike the Nizwani School of thought, there is no clear evidence why the Rustaqi School was named after Rustaq town. It suppose to be called Bahla School of the thought as most of its member were from Bahla. 6. Internal and external reasons were behind the existence of Fiqh Encyclopedias.