In my view, the first coat of arms belongs to the Order of the Mercy (Mercè, in Catalan), founded in Barcelona, Catalonia, in 1238 to redeem captives taken on our wars against the Islam. It was widely expanded in Southern Europe.
The upper half (that, properly, should have a red background or "field") is the white cross of Barcelona Cathedral where it was founded by Sant Pere Nolasc (Saint Peter Nolasc) and Sant Ramon de Penyafort, as our cathedal is consecrated to the Holy Cross.
The lower half, for red (we call "blood") stripes or bars on a golden field shows the arms of Catalonia, as our king Jaume I (James the first), 1208-1276, took the order under his protection. It became one of the most important in the Catalan Kingdom. Later, it also expanded to America.
Our Lady of Mercy, (Mare de Deu de la Mercè)whose day is September 24th, is one of the patrons of the city of Barcelona. Mercè, Catalan for "Mercy" is a very popular name for Barcelona's women (I've three generations of close relatives, named Mercè).
