It's the 1920's, Pancho Villa is gone, and Mexico is settling into a post-revolution form of democratic government. Vatican influence over the psyche of the country remains an enemy and so, power brokers south of the border have written a new constitution to include articles restricting the power of the church over the citizenry and to detach it from Vatican control. Back in the United States, Protestant evangelism is powerfully representative of the American Way, so the possibilities are a welcome sight to certain people of power interested in keeping the menacing spread of Catholicism throughout North America in check. If only a clandestine Mercenary Force could be dispatched to represent those American interests. Enter Coloradan, Charlie Coates, who stealthily managed the bloody John D. Rockefeller strikebreaking campaign during the infamous Colorado Coalmining Wars. The government of Mexico chooses to ignore the atrocities and battles of the early 20th Century Cristero War which claimed over 120,000 lives. It was a long and dirty war selectively forgotten by the official history curriculum. The Vatican Must Go is one surprising account of what might have brought about all-out warfare against government attempts to stamp out Catholic Church control over the soul of Mexico. This historical fiction novel by D. Grant Fitter joins his first novel, City of Promises, as another solid contribution to the Tales of Old Mexico sub-genre, written in the great tradition of Graham Greene, Gary Jennings, and Clifford Irving.