10. yüzyılda Türkistan coğrafyasında İslamiyet'in hızla yayılmaya ve Türklerin de topluluklar hâlinde müslüman olmaya başladığı görülür. İslamiyet'in kabulüyle gerçekleşen kültürel değişimin ilk izleri Kutadgu Bilig ve Dîvânu Lugâti't-Türk gibi eserlerden takip edilebilmektedir. Bu dönemde Oğuzların da hem bir devletleşme sürecine girdikleri hem de bir İslamlaşma sürecini yaşadıkları görülür. Oğuzların İslamlaşma sürecini nasıl yaşadıklarını gösteren önemli bir tanık, Türk kültürünün çok önemli bir temsilcisi olan "Dede Korkut Hikâyeleri"dir. İslamlık öncesi dönemde teşekkül eden "Dede Korkut Hikâyeleri", İslamlık sonrası dönemde yazıya geçirilmiştir. Buna bağlı olarak hem İslamiyet öncesi inanç izleri taşımakta, hem de İslam inancına ait ögeleri içinde barındırmaktadır. Bu yüzden eserde hem ağacın, suyun, dağın eski kutsiyetini koruduğu belirgin bir şekilde göze çarpar, hem de kahramanların arı sudan abdest alıp iki rekat namaz kıldığı görülür. İslamiyet'in kabulüyle, Türkçe metinlerde kullanılmaya başlanan "Allah" kelimesi yanında "Tanrı" kelimesi de kullanılmaya devam eder. "Dede Korkut Hikâyeleri"nin Dresden nüshasının 56 yerinde "Allah", 73 yerinde "Tanrı" kelimesi geçmekte; eserde, "kâdir Tanrı" ve "kâdir Allah"; "Allah Taâla kargayupdur" ve "Tanrı Taâla kargayupdur" şeklindeki ifadelerden "Allah" ve "Tanrı" kelimelerinin birbirinin yerine de kullanılabildiği görülmektedir. Yapılan bu çalışmada; "Dede Korkut Hikâyeleri"nde "Allah" kavramını karşılayan kelimeler tespit edilmiş, tespit edilen bu kelimelerin değerlendirilmiş ve buna bağlı olarak bu hikâyelerdeki Oğuzların İslamlaşma sürecinde "Allah" kavramı algıları hakkında bilgilere ulaşılmaya çalışılmıştır

In the 10th century at the geography of Turkistan, it is seen that Islam had started to spread rapidly and Turks too, had started to become muslim by groups. The first trace of the cultural change together with the acceptance of Islam can be followed in works such as Kutadgu Bilig and Dîvânu Lugâti’t-Türk. In this period it is seen that the Oghuzs had entered a process of becoming a state, together with a process of islamisation. An important witness that shows how the Oghuzs lived the process of islamisation, is the “Dede Korkut Stories” which is an important representative of the Turkish Culture. “Dede Korkut Stories”, which took shape before the Islamic period, had been written down on paper after the Islamic period. In respect to this, it carries both the traces of pre Islamic belief and the concepts of Islamic belief. That is why in the work it can both prominently attract the attention that the trees, water, mountain protects its holiness, and it can be seen that the characters perform an ablution from pure water and perform a two-rakat prayer. Together with the acceptance of Islam, next to the “Allah” word, which had been started to be used in Turkish texts, the “Tanrı” word had also started to be used. In the Dresden version of “Dede Korkut Stories”, the word “Allah” has been used in 56 places and the word “Tanrı” has been used in 73 places; due to the statements of “kâdir Allah” and “kâdir Tanrı”; “Allah Taâla kargayupdur” and “Tanrı Taâla kargayupdur” it can be seen in the work that the words “Allah” and “Tanrı” are interchangeable. Structures in this study; “Dede Korkut Stories” in “God” satisfies the concept of words have been identified, detected context in which they use these words and their usage formats are evaluated and accordingly Oguz of the Islamization process in this story, “God” tried to obtain information about the concept of perception In the 10th century at the geography of Turkmenistan, it is seen that Islam had started to spread rapidly and Turks too, had started to become Muslim by groups. The first trace of the cultural change together with the acceptance of Islam can be followed in works such as Kutadgu Bilig and Dîvânu Lugâti’t-Türk. In this period it is seen that the Oghuzs had experienced a process of becoming a state, together with a process of Islamisation. After dwelling on the cities, it is seen that the Islam became more widespread in Oguzh society. This may be the result of the fact that there were many Muslims in places where Oguzh society settled in. While Turks became Muslim, they didn’t see any difference between their own “Tanrı” and “Allah” term in Islam. There are some similarities between the term “Tanrı” and “Allah”. For this reason, Turks hadn’t objected to use the term “Tanrı” instead of “Allah” for a long time. This may be guested as an effective reason of Islam’s spreading among Turks. The term “Tanrı” in non-Islamic Turks were sharing many similarities with the term “Allah” in Islam, so it can be said that Turks’ Gök Tanrı belief resembled “Allah” belief in Islam. It has been seen that the words of “Allah” and “Tanrı” was used interchangeably in texts written after Islam. One of these texts is “Dede Korkut Stories”. “Dede Korkut Stories” which are the most important and valuable agents of Turkish Culture is a substantial witness showing how Oguzhs experienced the phrase of becoming Muslim. The Book Dede Korkut started to form in 9-11 centuries around adventures of Sir Derya (Seyhun) tribes, and was put down on paper by an unknown writer who added the adventures happening in minor Asia geography in 14. and 15. Centuries. “Dede Korkut Stories” consisting of Pre-Islam Period were put on the paper in post Islam period. As a result, it both carries traces from pre Islamic period and includes items related to Islam belief. Hence, both the trees, water and water protect their divinity and the characters perform an ablution and perform two rakat prayers. It is known that Turks who spread different geographies because of different reasons bring their pre-Islamic beliefs to the present time with the difference of the prevailing time and place by chancing into different types despite the modernization. Despite everything, the importance given by Oghuzs in “Dede Korkut Stories” to the term of “God” can be counted as the implication of their having a strong Islam belief. The idiom ‘“Allah Allah dimeyince işler onmaz (2-11)” is a good example of this situation. It has also been seen that the words defining the term of “God” can be used interchangeably, and they are generally used in consecutive sentences in ‘Dada Gorghut stories.’ In the study, in respect to the words which are used to correspond to the concept of “God” and their form of usage, in the Oghuzs in the “Dede Korkut Stories”, the perception of the concept of “God” has been focused on and in respect to this, the state of the belief perception of the Islamisation period of the Oghuzs’ in the stories, have been evaluated. With this aim, the books consisting of two volume named as “Dede Korkut Kitabı I” (Ergin, 1997a) and “Dede Korkut Kitabı II” (Ergin, 1997b) was used, and “Dede Korkut Kitabı I” was taken as a basis while showing the line and foil numbers of the sentences related to the topic according to Dresden copy. For example (2-11) shows the eleventh line number of the second foil according to Dresden Copy. Conclusion The words of “Allah”, “Tanrı”, “Kâdir”, “Yaradan”, “Hak” and “Rab” was used to meant “God” in “Dede Korkut Stories”. Words of “Kâdir”, “Yaradan”, ve “Aziz” was also used ecpress the quality of “God” term. The vocabularies of 56 “Allah”, 73 “Tanrı”, 16 “Kâdir”, 4 “Yaradan”, 18 “Hak” ve 4 “Rab” which countervail the term of “God” was confirmed in the text. 17 times “Kâdir” and 4 times “Yaradan” words were used to express the quality of the term “God”. Except for them, when we look at the other words defining the quality of term “God”, the word “Tâala” which is a foreign word was the most widely used term and was used 36 times, 22 times as “Allah Tâala”, 4 times as “Tanrı Tâala” and ten times as “Hak Taala”. It was seen that both same contexts having the same meaning and different contexts having the same meaning were used to imply the term of “God” in the text. It was also seen that sometimes the different and similar context were same, and sometimes the same expressions was repeated. The words giving the meaning of “God” were used in a certain situation, and with a certain verb. The words meaning the term “God” which was used sometimes with a word or word group showing quality, or was used without expressing and quality was also used to express a certain situation in the same context with a certain verb or noun. Oghuzs in “Dede Korkut Stories” used the verbs meaning the term of “God” with similar meanings and similar duties. The words expressing the term of “God” were interchangeably, and when they were chanced in the sentence, there was no difference in the meaning. The importance that was given to the term of “God” by Oghuzs in “Dede Korkut Stories” can be counted as their having a strong Islamic Belief. For this reason, it can be said that they have a very high belief level. The lacking of the knowledge and applications related to Islam such as how to fast, give alms, perform salaat can be associated with the fact that they have no relation with the events which consist of the topic of most stories