Royal is returning to the club he worked at as an assistant in 2000, the last time the Dees made the grand final.
The 48-year-old comes to the club from the Saints, where he worked in 2010 as a development coach, and Richmond, where he was a senior assistant to Terry Wallace.
He has also been at North Melbourne and the Western Bulldogs (also with Wallace).
As a player, he notched up 199 appearances for Footscray from 1983 to 1993, winning their best and fairest award in his first year, and he represented Victoria eight times and was selected All Australian once, in 1986. He was also named as the rover in the Bulldogs' team of the century.
Royal said he was rapt to be returning to the Dees.
"I was very fortunate to work with a very good football team over the last 12 months, however an opportunity presented itself to work with an up and coming and exciting team," he said.
"I look forward to working with the club to build a successful team."
