Why are the flags of the US State of Texas and the independent nation of Chile so similar? Coincidence or do they share a common heritage? Also, as a side question: Why do so many nations/states use the red, white, and blue color scheme, many of them with one or more white stars, the stars and bars?
There is no direct relationship between the designs of the flags of Texas and Chile, sometimes flags are just similar :) Both were created after independence from Mexico and Spain. However, both were designed independently and separately.
The Chilean Flag is the older of the two, it was first used in 1817. The Texan flag was first officially flown in 1838.