"Even before Riesling, Kleinberger was grown as the main variety on the Rhine and Moselle. He came to the Moselle with the Trevorians. Due to its high frost resistance and adaptability, it experienced a renaissance in the Little Ice Age. (15th to 19th century) In mixed movements, he gave the Silvaner an additional bouquet. Until its final destination in 2007, this very old grape variety was considered extinct." (https://historische-rebsorten.de/rebsorte/gelber-kleinberger/)