The US foot has always been defined by the meter. Originally, Thomas Jefferson set the foot to be exactly .3 meter. The science of surveying and measurement weren't great in the late 18th and early 19th c, so the definition of the meter changed; by then, the US surveys were too far along to change.

My family has been involved with surveying on-and-off for ~100 years. I hated grabbing measuring tapes as a kid, because the "foot" or the "inch" was always sone batshit crazy thing. Like: decimal foot based on a 30cm foot; the "inch" is 3cm.