If I recall correctly, Squier started in Japan and eventually moved to Korea when Japanese production became too costly/cut too close to US production quality. Squier was eventually moved out of Korea to Mexico, because Fender wanted to monitor Squier much more closely as a second brand. A few years into Mexican Squier production, there was a plant fire and Squier production was moved to the main US Corona plant for a short time. A lot of these US Squiers used seconds and leftover parts from actual Fender guitar production lines. Once the Mexican facility was rebuilt, Mexican Squier production resumed in the mid 90's, only for Fender to promote the Mexican facility towards producing main line Fenders. Squier was moved back to Korea where they built low-end, as well as high-end Squiers via the Pro Tone series. Squier was eventually moved out of Korea because of cost cutting and is now being sourced to several different plants in China (Affinity, Standard, Classic Vibe), Indonesia (Affinity, Standard, Vintage Modified) and India (Vintage Modified).
Summary: Squier started from Japan then moved to > Korea > Mexico > US > Mexico > Korea > China, Indonesia and India