Yodeling is a musical tradition that evolved in the Alps. Technically, it’s a singing style that involves rapid switches between the low-pitched “chest register” and the high-pitched, falsetto “head register” while singing meaningless syllables, and its name is descriptive of the sorts of sounds made by yodelers. (“Yodel-ay-ee-oo!”) It was used by shepherds for centuries before becoming part of a broader folk music tradition in Germany, Austria and Switzerland in the 1830s.
From there, it made its way to the US. In the early 20th century, the pioneering country musician Jimmie Rodgers saw a troupe of Swiss yodelers performing in a church, and incorporated their vocal styles into his blues- and country-influenced performances. His series of 13 yodeling songs were known as the “blue yodel” songs.
Rodgers had an impact around the world, but two influences strike me as particularly strange.
First, Rodgers’s recordings made their way to Kenya in World War II, when British missionaries played recordings of various American musicians to local tribespeople. Of all the records, they loved Rodgers’s yodelling the most; pronouncing Jimmie Rodgers as “Chemirocha”, they attributed his vocalisations to his being half man, half antelope. This influenced their own singing, and their songs were recorded in turn by the ethnomusicologist Hugh Tracey in the 1950s.
Second, Rodgers influenced Indian music. The singer Kishore Kumar heard his music in childhood, and incorporated yodelling into his performances. He went on to be one of the most prolific and famous playback singers in Bollywood, recording countless soundtracks and songs over a forty-year career, and influencing generations of singers who followed him.