Complex sentence: The American Eagles primarily compete in the Division I Patriot League, having previously been members of the East Coast Conference (ECC) from 1965 to 1984 and the Colonial Athletic Association (CAA) from 1984 to 2001.
Split into simpler sentences: The American Eagles primarily compete in the Division I Patriot League. They were previously members of the Colonial Athletic Association (CAA) from 1984 to 2001.