The diatonic acccordian was designated the official musical instrument of Louisiana in 1990. The diatonic accordion (also called a "squeeze box" or "Cajun accordion") arrived in Louisiana from Germany in the mid to late 1890's and by the early 1900's had become a key element in Cajun music.
Although small, the Cajun accordion has more sound power and volume than a piano key accordion, but less range (diatonic means: "of or using only the eight tones of a standard major or minor scale without chromatic variations").
The accordion offered more reliability than the fiddle - it could be a serious problem when a fiddler broke a string and the closest music store was hundreds of miles away. The Cajun accordion has four reeds for each note - even if some reeds were broken, enough still remained to make music. It was also the only instrument which tolerated the humidity of the region without ill effect.