Disputatio:Index regum Hispaniae

Hispaniarum

Hmm, looks like at least in the era of Philip III and IV, and presumably not just them, the title was Hispaniarum Rex. E.g. http://www.maravedis.org/felipe3.html --Iustinus 08:20, 27 Ianuarii 2007 (UTC).

Philip II and Charles I also had in their coins "Hispaniarum rex", bu this is aparently an old archaism that refers to the "2 Spains", citerior and ulterior. These references appear as early as in Isidore--Xaverius 08:40, 14 Maii 2007 (UTC)