351.) proved that the names of Isabella and Elizabeth were in ancient
times used indifferently, and particularly in the reigns of Edward I.
and Edward III. Mr. Hardy says in his evidence:--

"In the British Museum there is a Latin letter of Elizabeth of
Austria, Queen of Charles IX. of France, to Queen Elizabeth of
England. In the Latin she is called Elizabetha, and she signs
her name Ysabel. In the _Chronicle de St. Denis_, in the year
1180, it is stated, 'Le jor martmes espousa la noble Roine
Ysabel,' 'Upon this day, Queen Elizabeth was married;' and in
_Rigordus de Gestis Philippi Augusti Regis Francois_ it is
stated, 'Tune inuncta fuit Elizabeth uxor ejus venerabilis
foemina;' and Moreri says she is called 'Elizabeth or Izabeau de
Hainault, Queen of France, wife of Philippe Auguste.' Camden, in
his _Remains_, says, 'Isabel is the same as Elizabeth;' that the
Spaniards always translate Elizabeth into Isabel, and the French
into Izabeau. I have seen in the British Museum a deed, in which
the name Elizabetha is written in Latin; on the seal it is
Isabella. In the _Inquisitiones post Mortem_ I have frequently
seen Ysabella returned in one country and Elizabetha in an other
for the same person. I have something like a dozen other
instances from Moreri, in which he says that Elizabeth and
Isabella or Isabeau are the same. Elizabeth or Izabeau de
France, dau. of Lewis VIII. and Blanche of Castella; Elizabeth
or Isabelle d'Aragon, Queen of France, wife of Philippe III.,
surnamed le Hardie; Elizabeth or Isabeau de Bavière, Queen of
France, wife of Charles VI.; Elizabeth or Isabeau d'Angoulême,
wife of King John of England; Elizabeth or Isabeau de France,
Queen of England, dau. of Philippe IV.; Elizabeth or Isabelle of
France, Queen of Richard II.; Elizabeth or Isabelle de France,