as on hussars...it seems to be going back to the Balkans...
Border soldiers or granizars / grenzer...local lads protecting the borders and being a buffer. A little different to the Pandurs but similar in roles and resposibilities.
Some reading ; a book by Major General of the Hussars Charles-Emmanuel de Warnery "Remarks On Cavalry "
https://en.wikipedia.org/wiki/Hussar