Church weddings started as back in the eighth century.
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The wedding ceremonies came in two parts; betrothal and the actual wedding.
The marriage was just an agreement between the families involved. It was private and communal.
Later in the middle ages, the only thing that held more power than the parents were the Feudal lords in Europe. The parents would ask a lord for permission for their children to marry.
As the western Europe and Roman empire continued being Christianized, the church began to reach it’s influence in all aspects of life; finances, politics and family. Eventually, marriage became a combination of family traditions church and state.
By twelfth century, the church wedding was fully established inside the church with the priest pronouncing blessings. The idea of a Christian marriage was important that faith should be practiced in the home.
Until twentieth century, church was expected place for weddings.
Fast forward to now, Church isn’t the only place for weddings as barns, sports arena, beach or any desired location can be used provided there’s a priest to wed the new couple since all that really matters is that couple is ready and prepared for marriage.