15世纪中期（13世纪中期作为姓氏），“在圣瓦伦丁节选择的爱人”，来自晚期拉丁语 Valentinus，是两位早期意大利圣人的名字（来自拉丁语 valentia “力量，能力”；参见 valence）。在这一天选择爱人的习俗起源于14世纪的英语和法语宫廷圈。
“发送给爱人的信件或卡片”的意义记录于1824年。人们说这一天的浪漫联想来自于鸟类开始选择配偶的时节。
For this was on seynt Volantynys day
Whan euery bryd cometh there to chese his make.
[Chaucer, "Parlement of Foules," c. 1381]
可能这个日期是在发明这一习俗的法国地区非正式的春季第一天（许多保存下来的中世纪日历将春季的开始算作2月7日或22日）。没有证据将其与罗马的 Lupercalia（18世纪的理论）或与任何圣人的浪漫或鸟类特质联系起来。这一天发送特殊卡片或信件的习俗在1840-1870年左右在英格兰盛行，20世纪初左右衰退，并在1920年代复兴。
To speak of the particular Customs of the English Britons, I shall begin with Valentine's Day, Feb. 14. when young Men and Maidens get their several Names writ down upon Scrolls of Paper rolled up, and lay 'em asunder, the Men drawing the Maidens Names, and these the Mens; upon which, the Men salute their chosen Valentines and present them with Gloves, &c. This Custom (which sometimes introduces a Match) is grounded upon the Instinct of Animals, which about this Time of the Year, feeling a new Heat by the approach of the Sun, begin to couple. ["The Present State of Great Britain and Ireland" London, 1723]
