A later Turki word "Altishahr", meaning "Six Cities", came into vogue during the rule of the 19th century Tajik warlord Yaqub Beg, which is an imprecise term for certain western, then Muslim oasis cities. Shoqan Walikhanov names them as Yarkand, Kashgar, Hotan, Aksu, Uch-Tufpan, and Yangi Hisar; two definitions by Albert von Le Coq substitute Bachu (Maralbishi) for Uch-Turfan or Yecheng (Karghalik) for Aksu. During Yaqub's rule, Turfan substituted for Uch-Turfan, and other informants identify seven, rather than six cities in "Alti-shahr". The borders of Alti-Shahr were better defined than those of Moghulistan, with the Tian Shan marking the northern boundary, the Pamirs the western, and the Kunlun Shan the southern. The eastern border usually was slightly to the east of Kucha.