A vassal state is any state that is subordinate to another. The vassal

Vassal

A vassal or feudatory is a person who has entered into a mutual obligation to a lord or monarch in the context of the feudal system in medieval Europe. The obligations often included military support and mutual protection, in exchange for certain privileges, usually including the grant of land held...

 in these cases is the ruler, rather than the state itself. Being a vassal most commonly implies providing military

Military

A military is an organization authorized by its greater society to use lethal force, usually including use of weapons, in defending its country by combating actual or perceived threats. The military may have additional functions of use to its greater society, such as advancing a political agenda e.g...

 assistance to the dominant state when requested to do so; it sometimes implies paying tribute

Tribute

A tribute is wealth, often in kind, that one party gives to another as a sign of respect or, as was often the case in historical contexts, of submission or allegiance. Various ancient states, which could be called suzerains, exacted tribute from areas they had conquered or threatened to conquer...

, but a state which does so is better described as a tributary state

Tributary state

The term tributary state refers to one of the two main ways in which a pre-modern state might be subordinate to a more powerful neighbour. The heart of the relationship was that the tributary would send a regular token of submission to the superior power...

. In simpler terms the vassal state would have to provide military power to the dominant state

Ancient China

From the time of the Zhou Dynasty

Zhou Dynasty

The Zhou Dynasty was a Chinese dynasty that followed the Shang Dynasty and preceded the Qin Dynasty. Although the Zhou Dynasty lasted longer than any other dynasty in Chinese history, the actual political and military control of China by the Ji family lasted only until 771 BC, a period known as...

 (1046–770 BCE) until the Han Dynasty

Han Dynasty

The Han Dynasty was the second imperial dynasty of China, preceded by the Qin Dynasty and succeeded by the Three Kingdoms . It was founded by the rebel leader Liu Bang, known posthumously as Emperor Gaozu of Han. It was briefly interrupted by the Xin Dynasty of the former regent Wang Mang...

 (206 BCE –220 CE), a varying number of vassal states existed in Ancient China

China

Chinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...

.
These ranged in size from small city states to vassals which controlled large swathes of territory such as the States of Chu

Chu (state)

The State of Chu was a Zhou Dynasty vassal state in present-day central and southern China during the Spring and Autumn period and Warring States Period . Its ruling house had the surname Nai , and clan name Yan , later evolved to surname Mi , and clan name Xiong...

 and Qi

Qi (state)

Qi was a powerful state during the Spring and Autumn Period and Period of the Warring States in ancient China. Its capital was Linzi, now part of the modern day city of Zibo in Shandong Province....

. One of these vassal states would go on to conquer China and unite the country under the first emperor Qin Shi Huang

Qin Shi Huang

Qin Shi Huang , personal name Ying Zheng , was king of the Chinese State of Qin from 246 BC to 221 BC during the Warring States Period. He became the first emperor of a unified China in 221 BC...

.

Ottoman Empire

The Ottoman Empire

Ottoman Empire

The Ottoman EmpireIt was usually referred to as the "Ottoman Empire", the "Turkish Empire", the "Ottoman Caliphate" or more commonly "Turkey" by its contemporaries...

 (1299–1923 CE) controlled a number of tributary or vassal states in the peripheral areas of its territory. Vassalage took a number of different forms with some states permitted to elect their own leaders. Other states paid tribute for their lands.
The ottoman empire controlled many states such as during the 1700's the Berber people

Berber people

Berbers are the indigenous peoples of North Africa west of the Nile Valley. They are continuously distributed from the Atlantic to the Siwa oasis, in Egypt, and from the Mediterranean to the Niger River. Historically they spoke the Berber language or varieties of it, which together form a branch...

 and Crimean Khanate

Crimean Khanate

Crimean Khanate, or Khanate of Crimea , was a state ruled by Crimean Tatars from 1441 to 1783. Its native name was . Its khans were the patrilineal descendants of Toqa Temür, the thirteenth son of Jochi and grandson of Genghis Khan...

. After the Crimean war the Ottomans were made a 'protectorate' to the French colonial empire

French colonial empire

The French colonial empire was the set of territories outside Europe that were under French rule primarily from the 17th century to the late 1960s. In the 19th and 20th centuries, the colonial empire of France was the second-largest in the world behind the British Empire. The French colonial empire...

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Today, more common terms are puppet state

Puppet state

A puppet state is a nominal sovereign of a state who is de facto controlled by a foreign power. The term refers to a government controlled by the government of another country like a puppeteer controls the strings of a marionette...

, protectorate

Protectorate

In history, the term protectorate has two different meanings. In its earliest inception, which has been adopted by modern international law, it is an autonomous territory that is protected diplomatically or militarily against third parties by a stronger state or entity...

 or associated state

Associated state

An associated state is the minor partner in a formal, free relationship between a political territory with a degree of statehood and a nation, for which no other specific term, such as protectorate, is adopted...

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