Letter of Nanse

The letter of Nanše was one of the first attempts to agree on common standards of weights and measures, specifically "to weigh silver with standard weights" and to "standardize the size of reed baskets" in order to promote peaceable trade between city-states of ancient Mesopotamia, the area of modern-day Iraq, eastern Turkey, and southwestern Iran drained by the Tigris and Euphrates rivers. Michael Roaf's "Cultural Atlas of Mesopotamia" includes a timeline for the development of these standards, and Ken Kitchen has discussed methods for dating contracts and other commercial records by the form of the units of measure used in them.

In ancient Mesopotamia several different standards of weights and measures were in use. In the twenty-second century BCE, during the reign of Gudea, a petty king of Lagash, a city-state near the confluence of the Tigris and Euphrates, a proposal for reform, the so-called letter of Nanše, was circulated between the various city-states of the region. From this tentative beginning, eventually, a set of standards evolved that lasted for centuries and expanded to include most aspects of weighing and measuring in commercial contexts. The basis of these standards was the sexagesimal (base 60) numbering system then prevailing in the region.

Standards of this sort established exchange rates or values, as well as definitions of land areas, so that exchanges of commodities (like silver or grain or olive oil) and real estate could be accomplished without undue bickering over price.

The modern-day system of international weights and measures is enforced by the Bureau international des poids et mesures (BIPM), and it is based on the International System of Units (SI), commonly known as the Metric System. This modern regime can trace its lineage to a decimal system of standards adopted in post-revolutionary France, which, in turn, was based on aspects of the ancient Roman system. The Romans derived their weights and measures, in large part, from the Greeks. The Greek system was inherited from the Hittites, and (in successively older iterations) the Hurrians, the Akkadians, the Babylonians, and the Sumerian-Chaldean system, which the letter of Nanše may have been instrumental in starting.

A hymn to Nanše (Nanše A)

The following is a possible translation of the relevant portion of the ancient cuneiform text:Fact|date=September 2007

: Lines 232-240. At the house which has been granted powers from the abzu,: in Sirara, the gods of Lagash (Lagaš) gather around her. : To weigh silver with standard weights, : to standardise the size of reed baskets, : they establish an agreed ban measure throughout the countries. : The shepherd, the expert of the Land, the wise one (?) of the countries, : Ištaran, who decides lawsuits justly, who lives in the Land …… Ningshishzida ……. : - "2 lines unclear" -: Lines 241-250. To weigh silver with standard weights: to standardise the size of reed baskets, : they establish an agreed ban measure throughout the countries. …… : of (?) all the great rites. : - "1 line unclear" -: After …… in (?) the established storerooms, : the lady of the storerooms …… her lofty …… : with (?) vessels with ever-flowing water and : with (?) …… of (?) reed containers which never become empty, : she ordered her herald, lord Ḫendursaĝa to make them profitable (?).

See also

History of measurement