At least around the time of Roman rule the day was divided into what are called "canonical hours" so that there were 12 equal hours during the day and 12 equal

At least around the time of Roman rule the day was divided into what are called "canonical hours" so that there were 12 equal hours during the day and 12 equal hours during the night. This meant that during the summer the hours during day would be longer than the hours during the night and vice versa during winter. But keeping track of the hours themselves was a bit hard, so usually people only referred to three major hours of the day: Terce, around mid-morning; Sext, at noon; and None, around mid-afternoon. So yes, the hours of the day were absolutely dependent on the latitude (along with the day of the year).