This uniquely patterned flower goes by several names including Checkered Lily, Snake’s Head Fritillary, and Guinea Hen Flower. It is Fritillaria meleagris, the genus name meaning (basically) checkered and the species name referring to guinea fowl. This plant is native to Eurasia from the UK across into western Russia. It is also widely grown as a spring bulb in gardens all across the USA. Certainly planting a few of these bulbs would provide a new conversation starter for any garden!
KEW Botanical Gardens
Encyclopedia of Life
Wikipedia
Pacific Bulb Society
Paghat’s Garden