The border between Spania and Visigothic kingdom was not closed. Travel between the border for personal and mercantile reasons was allowed and the two regions experienced prolonged periods of peace. The ease of traversing the frontier was noted by the exiled Leander, whose brother more than once crossed it without hindrance. The border had been determined by a treaty ("pacta") between Athanagild and Justinian I, but the date of the treaty is still debated. It may have been part of the initial conditions of Byzantine assistance in 551 or 552 or it may have been a product of the war between Goth and Roman in 555 or later. It was certainly signed before Justinian's death in 565. The legitimacy of the "pacta" was recognised as late as the 7th century, which accounts for the ease of travel and trade.