Since 2007, the NFL has sent teams across the Atlantic to play games in London's Wembley Stadium in an initiative called the NFL International Series. During the inaugural season in '07, Londoners watched the New York Giants defeat the Miami Dolphins 13-10. The New Orleans Saints beat the San Diego Chargers in 37-32 in '08 and then the New England Patriots rocked the Tampa Bay Buccaneers 35-7 in '09. The NFL increased the number of games to two in '13, featuring the Jacksonville Jaguars and San Francisco 49ers, then the Minnesota Vikings and Pittsburgh Steelers.
In '14, the NFL added yet another scheduled game:
September 28: Miami Dolphins at Oakland Raiders
October 26: Detroit Lions at Atlanta Falcons
November 9: Dallas Cowboys at Jacksonville Jaguars
All the while the Cincinnati Bengals have had relatively nothing to do with the International Series.
According to the new deal that the Cincinnati Bengals reached with Hamilton County regarding stadium upgrades, the county "is allowing the team to play two international games as the 'home' team. The lease calls for the county to profit from tickets and parking during all home games, which won't be possible if they play outside the country. The team can play those games during any five consecutive year period," writes the Cincinnati Enquirer.
The team's statement with Hamilton County says in part:
The agreement also allows the Bengals to participate in the NFL’s International Series games. Given the league’s growth overseas, the Bengals can now take the Cincinnati brand abroad on a periodic basis, consistent with the other teams in the league.
Essentially, even though a game could be played overseas, Hamilton County would still get the money they were normally receive if the game were played in Cincinnati.