Short answers, pulled from the story.
Denver City was established on the 22nd of November 1858 by General William Larimer and Captain Jonathan Cox. They staked a claim on a bluff overlooking the confluence of the South Platte River and Cherry Creek to create a new townsite.
The Treaty of Fort Wise signed on the 18th of February 1861 forced six Southern Cheyenne chiefs and four Arapaho chiefs to cede more than 90 percent of their designated lands including modern Denver. This conflict escalated into the Colorado War of 1864 and 1865 which included the Sand Creek massacre and ultimately cleared the area of its indigenous inhabitants by the end of the 1860s.
Citizens raised $300,000 within three days to fund a private railroad connection after routing through Cheyenne City threatened local prosperity. The Denver Pacific completed this link to the transcontinental railroad on the 24th of June 1870 ushering in an age of prosperity for the city.
Governor James Orman proclaimed the state constitutional amendment allowing home rule part of state law on the 1st of December 1902. This date marked when the City and County of Denver came into being separated from Arapahoe and Adams counties.
The Denver Broncos won back-to-back Super Bowls in 1997 and 1998 then again in 2015 while the Colorado Avalanche secured Stanley Cups in 1996 2001 and 2022. The Colorado Rockies won the NL Championship Series in 2007 and the Denver Nuggets claimed their first NBA championship in 2023.