At the time of acquisition, it operated sixteen casino properties, located in Colorado, Indiana, Iowa, Louisiana, Mississippi, Missouri, Nevada, Pennsylvania, and Ohio, and a horse track in Texas.

Pinnacle Entertainment traced its roots to June 10, 1938, when movie mogul Jack L. Warner opened the Hollywood Park Turf Club racetrack in Inglewood, California.

In September 2006, Pinnacle agreed to purchase the Sands Casino Hotel in Atlantic City, New Jersey and announced plans to replace it with a $1.5-billion resort.

On November 9, 2009, chief executive officer Dan Lee was forced out by the company's board of directors after reportedly physically confronting and threatening a St. Louis County official.

The company agreed in April 2012 to buy a 75.5% stake in Retama Park, a money-losing horse track in Selma, Texas, for $22.8 million.

The purchase was seen as a "defensive move" to help soften the blow if gaming in Texas were expanded and drew visitors away from Pinnacle's Lake Charles properties.

On June 26, 2012, Pinnacle sold Boomtown Reno for $12.9 million to M1 Gaming, the company of former Station Casinos executive Dean DiLullo.

[13] On August 14, 2013, Pinnacle bought Ameristar Casinos for $869 million plus $1.9 billion in assumed debt,[14][15] adding nine properties in Colorado, Indiana, Iowa, Missouri, Mississippi and Northern Nevada.

To gain FTC approval for the merger, Pinnacle agreed to sell its Lumiere Place property and Ameristar's under-construction casino in Lake Charles.