Why is it named as Six flags???

The original Six Flags park in Arlington is called Six Flags Over Texas. It refers to the flags of the 6 different nations that have governed Texas: Spain, France, Mexico, The Republic of Texas, the United States, and the Confederate States of America

Six Flags was in Texas, the Flags represented 3 states and 3 countries combined as equally to 6. They were Republic of Texas, United States of Confederate🇺🇸, United States 🇺🇸 🏳 + Mexico 🇲🇽, Spain 🇪🇸 and France 🇫🇷. Later began a new journey, to become a Theme park.

Got this from Google Search Why is six flags amusement park called six flags? Throngs flocked to Six Flags Over Texas when the park opened in 1961. Six themed sections, modeled after the culture of the six countries whose flags flew over Texas during the state's colorful history, created a spectacular and magical setting for guests — and provided the park's name & more info What are the six flags of six flags over texas? The flags represent the six nations that have claimed sovereignty over Texas. They are the Kingdom of Spain, the Kingdom of France, the Republic of Mexico, the Republic of Texas, the Confederate States of America and the United States of America.

Not sure why

Throngs flocked to Six Flags Over Texas when the park opened in 1961. Six themed sections, modeled after the culture of the six countries whose flags flew over Texas during the state's colorful history, created a spectacular and magical setting for guests — and provided the park's name.