We all look forward to a red letter day. It is a day of celebration, joy, or personal significance such as a wedding, graduation, promotion, or milestone achievement. But have you ever wondered why we describe such special occasions with the color red?
The expression dates back to medieval Europe, when important religious festivals and holy days were written in red ink on church calendars, while ordinary days appeared in black.
Red was chosen because it symbolized importance and was more visually striking. As printed calendars became common, the tradition continued, with holidays and other notable dates highlighted in red. Many printed calendars continue to display public holidays, festivals, and Sundays in red, preserving a custom that is centuries old.
By the 16th century, the phrase had evolved from a literal reference to calendars into a figurative expression for any memorable occasion. Today, people use it to describe milestones such as weddings, graduations, promotions, birthdays, or personal achievements.
