A millefleur (French "thousand flowers") is a motif of many small flowers and plants, often used as a background. This depiction is from The Unicorn in Captivity, the last piece of the Unicorn Tapestries, also known as the The Hunt of the Unicorn. The plants in the series are rendered with extraordinary accuracy—botanists have been able to identify 85 of the 101 plants depicted.
The Unicorn in Captivity is rife with symbols of fertility and marriage; many of the plants depicted here, such as wild orchid, bistort, and thistle, were used as fertility aids in the Middle Ages. The 'AE' cipher in the lower right corner refers to the original owners of the tapestries, who remain unknown, but leading theories suggest that the 'A' may have been Anne of Brittany.