"The purpose of the research is to offer a three-dimensional examination of a chosen population’s make-up, examining ethnicity, native language, and religious denomination during the 20th century in the Romanian Bihor County. This paper examines the changing process of how identity in Érselénd/Șilindru was influenced by outside forces coming from different social, political, religious, and even economic directions. The village was chosen, as it was originally a Ruthenian-speaking Greek Catholic settlement that moved to the Hungarian Kingdom centuries ago. They kept their religious identity but became Hungarian-speaking people. Then, during the twentieth century, this homogenous settlement, due to external political, historical, and economic influences, experienced a profound change to a degree that had not been predicted. However, this fragmentation into various Christian denominations, the changes of language and ethnic identity clearly demonstrates the complex history of the geopolitical region of Partium, Romania. Keywords: Greek Catholics, identity change, Ruthenians, minority, religion, ethnicity, Partium "