Frest (フレスト Furesuto) is a city mentioned in Fire Emblem: Thracia 776, although it is never visited or viewed in the game. It is notable for being the hometown of Asbel, whose father presided as a bishop there. Although not much information is revealed about the city, it can be assumed that it was free from military occupation and invasion for a time as it was referred to as a "free city."
According to the Illustrated Works timeline, Leif had come to hide in the city along with Finn, Nanna and Lachesis to avoid the empire during the years 766 to 768 under the protection of the bishop, who was presumably Asbel's father. During this time, Asbel became acquainted with Leif, who he befriended as well. Unfortunately, Leif's respite was short-lived when the citizens of the city feared the consequences of the prince's residence and informed the Empire, which sent soldiers that ambushed the city. The bishop stayed behind to give time to the others to flee, but was later captured and executed. It is unknown what happened to the city after this, as its fate is never referenced during the events of Thracia 776.
After the liberation wars end though, Asbel returns to the city to assume his father's position as a bishop of Frest. Later, he becomes famed throughout the continent as a talented sage as well.