The word "How" is used frequently as a greeting in representations of Native American

Indigenous peoples of the Americas

The indigenous peoples of the Americas are the pre-Columbian inhabitants of North and South America, their descendants and other ethnic groups who are identified with those peoples. Indigenous peoples are known in Canada as Aboriginal peoples, and in the United States as Native Americans...

 speech. According to the Oxford English Dictionary

Oxford English Dictionary

The Oxford English Dictionary , published by the Oxford University Press, is the self-styled premier dictionary of the English language. Two fully bound print editions of the OED have been published under its current name, in 1928 and 1989. The first edition was published in twelve volumes , and...

, the word was originally used by missionary Jean de Brébeuf

Jean de Brébeuf

Jean de Brébeuf was a Jesuit missionary, martyred in Canada on March 16, 1649.-Early years:Brébeuf was born in Condé-sur-Vire, Normandy, France. He was the uncle of the fur trader Georges de Brébeuf. He studied near home at Caen. He became a Jesuit in 1617, joining the Order...

 to indicate an interjection

Interjection

In grammar, an interjection or exclamation is a word used to express an emotion or sentiment on the part of the speaker . Filled pauses such as uh, er, um are also considered interjections...

 of approval used by the Wyandot (or Huron in French uses); the OED gives the transcription haau. It later became common in popular culture, used (perhaps inaccurately) as a greeting.

It was adopted from the Lakota Sioux word háu which is used by men as a greeting "hello", and is pronounced as the English "how".