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H an (n): The feudal domains ruled by daimyô are most commonly throughout Rokugani history referred to as han . During the age of Exploration, the term as fallen into relative disuse, and domains are instead referred to by a number of terms including:
kuni ("country", "state") (Much to the Crabs amusement)
ryô or ryôbun ("territory", "portion of territory") (the play on the term for coinage is often used in jokes)
shiryô ("private territory") (Typically used to refer to Samurai residences)
ie (“house”) (used to refer to peasant housing, usually farming housing)
zaisho ("place where one is resident") (often used interchangeably when referring to Merchant housing and places of business)
fu or seifu ( "government") (used to refer to governing clan residences or governmental buildings),
and kôgi ("government", "public affairs") (typically used when referring to Imperial Holdings), among others.
The use of these terms was often governed by omote and uchi (or "external" and "internal") concerns; a term such as kuni might be used in internal domain documents to refer to the domain, but when speaking to the Emperor about one's domain, kuni would be used to refer to Rokugan as a whole, and another term, such as zaisho , would be used to the daimyô's humble appointed territory
The han are largely autonomous in terms of their internal affairs, but were subject to numerous strictures originally imposed by Hantei III, as well as taxation and ritual obligations. Hantei XVI , officially acknowledged (for tax purposes and control) 185 major domains during his reign; by the reign of Hantei XX, the number of major domains stabilized around 260, but the total number of distinct domains that existed at one time or another over the course of Rokugani History exceeds 540.
Though many daimyô continue to hold their ancestral territory as their han , in theory all han a re fiefs granted by the Emperor of Rokugan. The Emperor reserves the right to give and take away lands from daimyô , and often makes use of this power, reassigning a given territory to a different samurai clan, and assigning the former lords of that territory to a different domain elsewhere in the archipelago, or simply denying them a territory entirely during political turmoil or as a possible reward for service. This occurred particularly frequently in the Reign of Hantei XVI and during the Heresy Era, with 281 instances of clans being moved from one domain to another, and 213 instances of clans losing daimyô status, and their domains, entirely during that fifty-year period. The latter was most often due to the absence of an heir; though Imperial policies were relaxed in later eras, initially, deathbed adoptions were not permitted.
The power or status of each han (and of their daimyô ) was determined by its kokudaka , normally a measure of agricultural or commercial production in units of koku ; in some cases, domains were assigned a kokudaka out of proportion to their agricultural production, in recognition of their importance strategically, diplomatically, or otherwise. The smallest domains, by definition, had a kokudaka of at least 10,000 koku , while the largest domain s, boast a kokudaka of 1,000,000 koku . The vast majority of domains were closer to the lower end of this range, and only a handful of domains were assessed in the hundreds of thousands of koku .
On the Kokuda :
Kokudaka (n): a measure of the agricultural production of a daimyô domain, or " han ," expressed as a measure of koku of rice. As a representation of the domain's wealth, kokudaka determined the amount of the domain's tax obligations to the shogunate, and the domain's status relative to other domains.
The smallest daimyô domains, by definition, possessed at least 10,000 koku , while some samurai retainers were granted sub-domains within a han , with a much smaller rating in koku . The majority of han were officially assessed at a kokudaka in the range of 10,000 to 200,000 koku , though the kokudaka of the most powerful domains exceeded 500,000 koku .
This figure, though ostensibly based on the actual agricultural production of the domain's territory, often did not change over the course of the period. A domain's kokudaka might be changed as a political reward or punishment, but the Empire does not engage in regular surveys of agricultural production, and did not update domains' kokudaka on the basis of their production.
Multiple different figures for the kokudaka thus often existed simultaneously for a single domain. The official figure determined and recognized by the Empire and used as a marker or indicator of the domain's wealth and status can be referred to as omotedaka , using the character omote , meaning "official," "surface," or "outside." Meanwhile, nearly all domains maintained their own internal figures for agricultural production, called uchidaka , using the character uchi , meaning "inside" or "internal."
The uchidaka was often a higher figure, more regularly assessed and more accurately reflecting increases and expansions of agricultural productivity within the domain. It was generally in the best interests of the domain to not report the higher figure, and to allow the omotedaka recognized by the Empire to remain at a lower figure, since this means lower tax payments owed by the domain to the Empire; though this seems deceitful or deceptive, such behavior is widely condoned by the Empire, as part of the philosophy of omote and uchi , allowing internal matters to remain relatively private, so long as a domain's obligations on the official, external are properly observed.