A flatbow is a bow with non-recurved, flat, relatively wide limbs that are rectangular in cross-section. Because the limbs are relatively wide flatbows will usually narrow and become deeper at the handle, with a rounded, non-bending, handle for easier grip. This design differs from that of a longbow, which has rounded limbs that are circular or D shaped in cross-section, and is usually widest at the handle. Flatbows are usually wooden selfbows (bows made of one solid piece of wood), though composite flatbows can and have been made in ancient and modern times.

Flatbows were used by Native American tribes such as the Hupa, Karok, and Wampanoag, prehistoric ancient Europeans, some inuit tribes, Finno-Ugric nations and a number of other pre-gunpower societies for hunting and warfare because they are easily crafted, and, unlike longbows, excellent flatbows can be made from nearly any type of wood.

Though many people think solely of longbows when wooden bows are mentioned, the flatbow is actually a superior bow design for many types of wood because the stress is more evenly spread out than in a longbow. A bow limb is essentially a flexed beam undergoing bending, and in any flexed beam the farther from the neutral axis (line in the middle of the flexing beam which is not under tension or compression: see diagram in Bending article) the more stress there is within the material. When a limb is rounded, as in a longbow, some wood “sticks out” farther from the neutral axis, and thus is put under greater stress. In a flatbow, the flat belly and back ensures that all of the most highly strained wood is a uniform distance from the neutral axis, minimizing stress and making weaker woods far less likely to fail (break or become permanently bent and lose the springiness needed in a bow).

Because yew, the wood of choice for English longbows, is light, resilient, and has exceptional compressive strength, the rounded design can be used to produce a smooth shooting, efficient, powerful bow. For more common, lower strength, hardwoods such as elm (a bow wood used in ancient Europe, as evidenced by bows pulled from European bogs), maple, and ash, the flatbow design must be employed to create a bow of equal power and efficiency. The flatbow design also lends itself to very dense, high strength woods such as hickory and especially osage orange (a wood favored by many Native American tribes for bow making).

• (1992) The Traditional Boyers Bible Volume 1. The Lyons Press. ISBN 1-58574-085-3

• Gray, David (2002) Bows of the World. The Lyons Press. ISBN 1-58574-478-6