Although not a 'Stan, Mongolia is culturally related to Central Asia. The only real difference is that Mongolia is predominantly Buddhist, while the 'Stans are predominantly Muslim. The Mongolian language has a vertical alphabet, but has officially used the Cyrillic alphabet since the 1920s.
The Uighur people of Northwestern China are also culturally related to the 'Stans.
Also, while on the other side of the Caucasus, Azerbaijan is culturally similar, but more secular. The former Soviet republic of Azerbaijan should not be confused with a province in Iran with the same name. Also, Tajikistan uses a language related to Persian, while the other 'Stans use languages related to Turkish.
Besides Turkish, the Kazakh, Turkmen, Uzbek, and Kyrgyz languages have the following "relatives": Finnish, Estonian, Hungarian, Mongolian, Uighur, and possibly even Korean and Japanese.
Also, I am focusing mainly on the former Soviet 'Stans--not so much Afghanistan or Pakistan (which, except for being predominantly Muslim, is almost identical to India).
Tim
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