(Please read from the start)
“Inscriptions describing the reforms of king Urukagina of Lagash (c. 2300 BC) say that he abolished the former custom of polyandry in his country, prescribing that a woman who took multiple husbands be stoned with rocks upon which her crime had been written.”
“Sumerian culture was male-dominated and stratified. The Code of Ur-Nammu, the oldest such codification yet discovered, dating to the Ur III, reveals a glimpse at societal structure in late Sumerian law. Beneath the lu-gal ("great man" or king), all members of society belonged to one of two basic strata: The "lu" or free person, and the slave (male, arad; female geme).”
“Marriages were usually arranged by the parents of the bride and groom;[53]:78 engagements were usually completed through the approval of contracts recorded on clay tablets. These marriages became legal as soon as the groom delivered a bridal gift to his bride's father.”
“From the earliest records, the Sumerians had very relaxed attitudes toward sex[57] and their sexual mores were determined not by whether a sexual act was deemed immoral, but rather by whether or not it made a person ritually unclean. […] . Prostitution existed but it is not clear if sacred prostitution did.”
>> I personally didn’t find anything indicating the practice of incest nor pedophilia in Sumer, but there are arguments about the existence of homosexuality.
“Language and writing
The most important archaeological discoveries in Sumer are a large number of clay tablets written in cuneiform script. […] A large body of hundreds of thousands of texts in the Sumerian language have survived, such as personal and business letters, receipts, lexical lists, laws, hymns, prayers, stories, and daily records. Full libraries of clay tablets have been found. Monumental inscriptions and texts on different objects, like statues or bricks, are also very common. Many texts survive in multiple copies because they were repeatedly transcribed by scribes in training. Sumerian continued to be the language of religion and law in Mesopotamia long after Semitic speakers had become dominant.”
“The Sumerian language is generally regarded as a language isolate in linguistics because it belongs to no known language family; […].”
A little detour:
https://en.wikipedia.org/wiki/Cuneiform
“Cuneiform[a] was one of the earliest systems of writing, invented by Sumerians in ancient Mesopotamia.[b][4][5] It is distinguished by its wedge-shaped marks on clay tablets, made by means of a blunt reed for a stylus. The term cuneiform comes from cuneus, Latin for "wedge”.
“Emerging in Sumer in the late fourth millennium BC (the Uruk IV period) to convey the Sumerian language, which was a language isolate, cuneiform writing began as a system of pictograms, stemming from an earlier system of shaped tokens used for accounting. In the third millennium, the pictorial representations became simplified and more abstract as the number of characters in use grew smaller (Hittite cuneiform). The system consists of a combination of logophonetic, consonantal alphabetic, and syllabic signs.”
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