The Rensselaer branch of the Church of Jesus Christ of Latter-Day Saints meets at 800 S. College Avenue. According to the "Church Services Directory" in the Rensselaer Republican, the branch president is Ronald Cameron. There is a Sunday Sacrament Meeting at 9:00 and there are other meetings on Sunday and during the week.
The members of the Church of Jesus Christ of Latter-Day Saints are colloquially called Mormons. The building that they occupy was formerly the building used by the U.S. Department of Agriculture, which is now on Drexel Drive. When I came to Rensselaer, a Dog and Suds drive in occupied the site.
The Church of Jesus Christ of Latter Day Saints was founded in the 19th century in the United States. The site www.mormon.org explains the Mormon understanding of its origin and connection to Protestant, Catholic, and Orthodox churches:
Following the death of Jesus Christ, wicked people persecuted and killed many Church members, and other Church members drifted from the principles taught by Jesus Christ and His Apostles. The Apostles were killed and the priesthood authority—including the keys to direct and receive revelation for the Church—was taken from the earth ( 2 Thessalonians 2:1–3). Because the Church was no longer led by priesthood authority and revelation, error crept into Church teachings. Good people and much truth remained, but the gospel as established by Jesus Christ was lost, resulting in a period called the Great Apostasy.The Mormons were persecuted in the eastern U.S., so many migrated to Utah, where they are the dominant religious group, as shown in the religious maps at Valparaiso University.
After centuries of spiritual darkness, a restoration of truth was needed. Under the direction of our Heavenly Father, the gospel of Jesus Christ was restored on the earth through the Prophet Joseph Smith. God has promised it will never be taken from His children again.
Wikipedia has a summary of beliefs and history.