Elizabeth f. Ancient Greek Ἐλισάβετ from Hebrew אלישבע 'my God is an oath'.
The name of the sister of Mary and mother of John the Baptist in the Bible, an 11th C queen consort of Norway, a 12th C German saint, two 13th C queens consort of Hungary, a 13th C queen consort of Serbia, a 14th C queen consort of Portugal and saint, a 14th C queen consort of Castile, a 14th C queen consort of Scotland, a 14th C queen of Denmark, a 14th C queen of Germany, a 14th C Holy Roman empress, two 14th C queens consort of Bohemia, a 14th C queen consort of Hungary, a 14th C queen consort of Hungary and Poland, a 14th C queen consort of Sicily, two 15th C queens consort of England, a 15th C queen consort of Germany, a 15th C queen of the Romans, a 15th C queen consort of Hungary, Bohemia, and Germany, two 15th C queens consort of Poland, a 16th C queen consort of Spain, a 16th C queen of England, a 16th C queen consort of France, and a 16th C queen consort of Poland. Wycliffite Bible (1395): Elizabeth.
The name Isabel was originally an Old Provençal form of Elizabeth; while it soon became treated as an independent name, the connection between the two was still known in England as late as the 16th C, where there are examples of the same woman being recorded as both Elizabeth and Isabel (see Withycombe s.n. Isabel(la)).