Sunday sporting events were not usually played until the early 20th century. In North America, they were prohibited due to blue laws at first, but then cities like Chicago, St. Louis, and Cincinnati later decided to legalize them. Other cities such as New York City and Philadelphia had intense political and court battles to legalize the games. Nowadays, professional sports leagues schedule games on Sundays in the United States, though this practice continues to be opposed by some Christian denominations upholding first-day Sabbatarian doctrine.