during the reign of the Golden Horde, whose inhabitants fully spread Islam and the closest predecessor of the Kazakh language to the Kazakh steppe. The modern Kazakh language is said to have originated in approximately 1465 AD during the formation of the Sunni Muslim Kazakh Khanate. Modern Kazakh is likely a descendant of both Chagatay Turkic as spoken by the Timurids and Kipchak Turkic as spoken in the Golden Horde. As a language that is mostly spoken by a deeply Muslim ethnic group, Kazakh uses a high volume of loanwords from Persian and Arabic due to the frequent historical interactions between Kazakhs and Iranian ethnic groups to the south. Additionally, Persian was a lingua franca in the Kazakh Khanate, which allowed Kazakhs to mix Persian words into their own spoken and written vernacular. Meanwhile, Arabic was used by Kazakhs in mosques and mausoleums, serving as a language exclusively for religious contexts similar to how Latin served as a liturgical language in the European cultural sphere. The Kazakhs used the Arabic script to write their language until approximately 1929. In the early 1900s, Kazakh activist Ahmed Baytursinuli reformed the Kazakh-Arabic alphabet, but his work was largely overshadowed by the Soviet presence in Central Asia. At that point, the new Soviet regime forced the Kazakhs to use a Latin script, and then a Cyrillic script in the 1940s in an effort to thoroughly Russianize them. Today, Kazakhs use the Arabic, Latin, and Cyrillic scripts to write their language. Writing system The oldest known written records of languages closely related to Kazakh were written in the Old Turkic alphabet, though it is not believed that any of these varieties were direct predecessors of Kazakh. Modern Kazakh, going back approximately one thousand years, was written in the Arabic script until 1929, when Soviet authorities introduced a Latin-based alphabet, and then a Cyrillic alphabet in 1940. Nazarbayev first brought up the topic of using the Latin alphabet instead of the Cyrillic alphabet as the official script for Kazakh in Kazakhstan in October 2006. A Kazakh government study released in September 2007 said that a switch to a Latin script over a 10- to 12-year period was feasible, at a cost of $300 million. The transition was halted temporarily on 13 December 2007, with President Nazarbayev declaring: "For 70 years the Kazakhstanis read and wrote in Cyrillic. More than 100 nationalities live in our state. Thus