Though the couple did not state their reasoning for choosing the baby's name, Chicago is also the city where her rapper father grew up.
And the five-day old baby appears to already have been given a nickname by her world-famous parents, with Kardashian West writing in a second tweet "North, Saint & Chi".
Kim and Kanye hired a surrogate mother to carry their third child after the beauty suffered complications whilst pregnant with four-year-old North and two-year-old Saint.
She added: "I'm so grateful for modern technology and that this is even possible. Welcome to the world, Chicago West!".
Kim Kardashian and Kanye West name newborn daughter Chicago West
Kim revealed the unique name in an early-morning blog post revealed in the form of a birth announcement.
Kardashian and West are no strangers to peculiar baby names. It will probably be a while until Kim and Kanye release photos of Chicago - and they certainly won't be selling it to the press.
Kardashian was reportedly in the delivery room when the baby was born. At different points, fans created conspiracy theories like Kylie Jenner being the surrogate to Kanye and Kim.
Ashley Boice, also in Chicago, said she isn't surprised by the unusual name.
In her message she wrote, "Kanye and I are happy to announce the arrival of our healthy, handsome baby girl". She also revealed Chicago was born January 15 and weighed 7 pounds, 6 ounces.
After Kim announced their pregnancy and we took a stab at guessing names.
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But again we're planing for it as if it's 100 percent. "We'd like to keep the government open". The Senate has until midnight Friday to pass the spending bill to avoid government shutdown .
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On 5/2/2017 announced a quarterly dividend of $0.08 1.27% with an ex dividend date of 5/31/2017 which will be payable on 6/2/2017. This repurchase authorization allows the financial services provider to buy shares of its stock through open market purchases.
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Neither of the companies offered official statements, but AT&T did tell Reuters that it's yet to make a decision on 5G suppliers. AT&T has also been warned to avoid using Huawei hardware for their subsidiaries like Cricket Wireless.