A Tale of Two Sisters
The Arendelle events take place many years before "A Tale of Two Sisters". The Enchanted Forest events take place after Geppetto's parents are turned into marionettes in "That Still Small Voice" (the marionettes can be seen in Rumplestiltskin's castle) and many years before Anna visits the Enchanted Forest in "White Out". The Storybrooke events take place after "Family Business".