Habsburg coat of arms

The central coat of arms: the double-headed Austrian eagle with a divided shield on its breast: on the left the crossbar (Habsburg), on the right the castle (Castile).

The split arms have been wielded by the Habsburg monarchs since the marriage of Philip the Handsome to Joan of Aragon and Castile.
The two other windows are decorated with the motto "PLVS OVLTRE" (= always onwards), applied to a band curled around two columns. These are crowned, the left one with the imperial crown, the right one with the royal crown. Above the band the Austrian imperial crown is once again displayed.
These represent the rocks on either side of Gibraltar, placed there by the god Hercules as a landmark. For a long time they were considered the end of the known world. It was not until around 1500 that explorers were able to put Charles V's motto 'Onward and upward' into action and acquire much unknown land.

Between the three windows there are two memorial stones. On the left there is the inscription
PH(ILIPU)S.ARCHID(UX).AVSTRI(A)E/HISPANIAR(UM).REX
i.e. Philips, Archduke of Austria, King of Spain, which must therefore refer to Aragon and Castile. The inscription on the right reads:
CAROLVS V PH[I(LIP)I FI]LIVS C(A)ESAR AVGVSTVS
i.e. Charles V, son of Philip, mighty emperor.
It therefore refers to the emperor of the German Empire, Charles V, who was the son of Philip the Handsome.
The busts of the above-mentioned sovereigns must also have been on display there. In 1781 there was in any case still talk of "...ou l'on voit encore dans le frontespice de l'hotel des commissaires-déciseurs du Duc de Brabant, les bustes de ces Princes et les armes de l'Empire en de l'Espagne."
And the same writer goes on to mention that these were placed to commemorate the visit of Charles V and Philips II in 1551, but this is probably incorrect for several reasons.
Philips II was only allowed to use the title as stated on the stone from 1556 onwards and if the renovation of the front facade coincided with that of the rear facade, on which the date 1545 can be found, then the Philips mentioned is certainly not Philips II, but almost certainly his grandfather Philips the Handsome.
The decorations with the personal motto of Charles V must almost certainly have been made during his reign. Philip II was then, so to speak, still out of the picture. That was different with Philip the Handsome. After all, he was the one who through his marriage had brought those two powerful empires together and was also allowed to use the imperial title.
Charles is referred to as Carolvs V. Logically, his son would then be referred to as Philip II, certainly to distinguish him from the other Philip mentioned, his grandfather.
Carolvs V Philipi Filivs; so why would Philip II not also have been called the son of Charles V? Surely it would not have been a disgrace with such a father.

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Above the gate in the courtyard there are two portrait medallions stating the year 1545. In that year those portraits can only be of the then rulers, Charles V and his sister Mary of Hungary, Grand Duchess of the Netherlands.

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