Complex sentence: The Aztec Club of 1847 is an historic society originally founded in 1847 by United States Army officers of the Mexican-American War, but it still exists as a hereditary organization including members who can trace a direct lineal connection to those originally eligible.
Split into simpler sentences: The Aztec Club of 1847 is an historic society founded in 1847 by United States Army officers of the Mexican-American War. It exists as a hereditary organization including members who can trace a direct lineal connection to those originally eligible.