The religion is a factor in the Starship Troopers franchise.
Starship Troopers novel[]
In the novel Starship Troopers, there are people of different religions. Each unit has a trooper, who is also a priest, possessing knowledge from various religions. For example, "Padre" Migliaccio is the chaplain of the Roughnecks.
Starship Troopers film universe[]
In the comic Starship Troopers: Brute Creations, a group of Mormons set a colony in Port Joe Smith on the planet Dantana, which is located in the Arachnid Quarantine Zone, in neglect of the warnings from the Federation government. The colony was later massacred and destroyed by the Arachnids force.
In the film Starship Troopers 3: Marauder, religions seem to be oppressed (but not banned, since Holly Little is a religious person). However, after the Battle of OM-1 and Enolo Phid becoming the Sky Marshal, religions are promoted and at least one is officially recognized by the authority. Lola Beck also becomes religious after the Battle of OM-1 and she asks Dix Hauser to marry her in a church.
In the film Starship Troopers: Invasion, Holy Man is a religious person and covers himself with tattoos across the culture.