This chant in the Paschal liturgy clip has some basic similarity in tone, pace and harmony to Rusyn or Galician chant patterns. I wonder if that is my ear or my imagination. Does anyone else familiar with these traditions hear this as well? The Italian or French influence would not have any impact, perhaps some monks relocated from east Europe after the Unia or were stuck there after the fall of Constantinople?
I really do not know but, for 7 years (1800-1807) the Septinsular islands were under the Russians (following the
Orlov Revolt), the Republic was officially a protectorate of the Russian crown. Now, one of the most prominent composers of Ecclesiastical hymns according to the Septinsular tradition is Themistocles Polycratis (here is a sample; it's the Vesperal "Praise the Lord from the heavens"):

And a video of the 15th Antiphon ("today He is suspended") composed by him:
http://www.youtube.com/watch?v=wnByeYDJAWc I'm personally unfamiliar with either the Rusyn or the Galician chanting tradition. Does it sound familiar?