English: pet form of Henry, sometimes used as an independent name. This was the usual English form of Henry in the Middle Ages and later, and was the form used by Shakespeare as the familiar name of the mature King Henry V (compare Hal). The intermediate form Herry probably arose from the French pronunciation with a nasalized vowel, or it may be the result of straightforward assimilation; the change of -er- to -ar- was a regular feature of late Middle English. Pet form: Hal.
A Dictionary of First Names, Oxford University Press, ISBN 0192800507
English: a perennially enduring given name, of Continental Germanic origin, composed of the elements haim home + ric power, ruler. It was introduced to Britain by the Normans, and has been borne by eight kings of England. In its various European cognate forms and in the Latin form Henricus, it has been borne by kings and princes in many countries of Europe. Henry the Fowler (c.876–936), Duke of Saxony, was elected King of the Germans and became the first of a long succession of bearers of the name to rule in central Europe. It was also borne by six kings of France and four kings of Castile and Leon. In England it was not until the 17th century that the form Henry (rather than Harry) became the standard vernacular form, mainly as a result of the influence of Latin Henricus and French Henri. Cognates: Irish Gaelic: Anraí, Éinrí. Scottish Gaelic: Eanraig. French: Henri. Italian: Enrico. Spanish: Enrique. Catalan: Enric. Portuguese: Henrique. Romanian: Henric. German: Heinrich. Low German: Henrik, Hinrich. Dutch: Hendrik. Scandinavian: Hen(d)rik. Polish: Henryk. Czech: Jindrich. Finnish: Heikki. Hungarian: Henrik; See also Imre.
Pet forms: English: Hal, Hank, Harry. Spanish: Quique. German: Heino, Heinz. Low German: Heiko, Henning. Danish: Henning.