Jyn Erso and Cassian Andor stole plans for the original Death Star destroyed in Episode IV. Bothans provided information about Death Star II that was destroyed in Episode VI.
MANY BOTHANS DIED TO BRING US THIS INFORMATION... BOTHANS?! CASSIAN ANDOR & JYN ERSO; (21 BBY - 0 BBY); (26 BBY - 0 BBY); YOUR SACRIFICE WILL NEVER BE REMEMBERED