The name Uzbekistan went on the map on 27 October 1924, when the Uzbek Socialist Soviet Republic was created. The name inside it is far older, and it may belong to one man.
The name has two parts. The ending -stan comes from Persian stân, "land or place of." Wordorigins notes that Persian also uses it in everyday nouns, such as rigestân, "place of sand," a desert. English uses -stan after a vowel or an aspirated consonant, as in Kazakhstan, and -istan after other consonants, as in Afghanistan.
The first part is the people, the Uzbeks. The American Heritage Dictionary traces Uzbek, through Russian, to Uzbek o'zbek, a word of medieval Turkic origin. It says the name is possibly after Özbeg Khan, who ruled the Golden Horde from 1313 to 1341. Britannica dates the start of his reign to 1312. In that account, Muslim Turkic tribes may have adopted the prestigious name of this Muslim ruler as their own.
Britannica is more direct. It says Özbeg's name "survives today in that of the Uzbek people and of Uzbekistan." Under him the Golden Horde, also called the Kipchak empire, in southern Russia, reached its greatest power. He converted to Islam but still welcomed Christian missionaries.
The khan's own name breaks down into two Old Turkic words. Öz means "self." Beg means "lord," the same word that became bey in Turkish titles. Read very literally, then, Uzbekistan is "land of the self-lords."
The modern borders are recent. In 1924 the Soviet state redrew Central Asia, dissolving the Turkestan republic and the people's republics of Bukhara and Khorezm. The new Uzbek republic was one result. It included Tajikistan until 1929, when that territory split off as its own Soviet republic.
On 31 August 1991 the republic renamed itself the Republic of Uzbekistan and declared independence. The Soviet Union dissolved that December.