We’ll also shed light on its impact on Las Vegas and its enduring legacy in the hospitality industry. In this article, we will delve into the intriguing backstory of the Flamingo Hotel, touching on the life of Bugsy Siegel, the construction process, the infamous opening, and its transformation over the years. If you’re short on time, here’s a quick answer to your question: The Flamingo Hotel was built by mobster Benjamin ‘Bugsy’ Siegel and his partners in the 1940s, marking a significant turn in the development of Las Vegas as a renowned resort city. The Flamingo Hotel, an icon in the Las Vegas landscape, has a colorful history as vibrant as its name suggests.