Simplify the following text for a Grade 12 native English-speaking person.
Original: Res Gestae Divi Augusti ( literaly ` The achievements of the divine Augustus ' ) , also known as Res Gestae and RGDA , was an autobiography and epitath written by Emperor Augustus following the tradition of writing about a dead person 's achievements and life but Augustus ' is the biggest by far .
Simplified: Res Gestae Divi Augusti , ( Latin : `` The Deeds of the Divine Augustus '' ) is the funerary inscription of the first Roman emperor , Augustus , giving a first-person record of his life and accomplishments . The Res Gestae is especially significant because it gives an insight into the image Augustus portrayed to the Roman people .