We are planning a medieval wedding, and would like our guests to dress in period costumes. Is it acceptable to ask our wedding guests to dress up in costume?
It is definitely ok to ask, but you can't exactly "require" it -- especially if you want people who may not be able to afford or otherwise get their hands on an appropriate costume to show up! Think of it as a "Black Tie Optional" event, where ideally you would like your guests to come dressed in ultra-formal attire, but you won't make them unwelcome if they don't. Perhaps you can provide some inexpensive costume props at your reception for those who show up without medieval garb.
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