On Surnames Knavs and Knaus
The surname Knavs is of Slovenian origin. A much more popular variant of this surname is Knaus or Knauss. Knauss is a common surname all around the western world, especially in Europe and the USA. Morphological change of the vowel "v" to "u" is common in the Slavic languages. The main cause of the modification is the similarity of writing. Another case is that is easier to pronounce “u” than “v”. One of the most famous examples is the toponym Supetar in Croatia. Its etymological root is the parish of Sv. Petar (St. Peter).
Thus, the surnames Knavs or Knaus or Knauss is the same root, mainly of German and Jewish origin.
Many people with surname Knaus and some of the surname Knavs emigrated from Slovenia and Croatia to the United States. In the first half of the 20th-century hundreds of Knaus, among whom were Knavs, emigrated from Yugoslavia, as recorded in the database Ellis Island. One of them is Johan Knavs who in 1926 sailed from Le Havre to New York. Slovene from Kočevja then had 51 years, and he was unqualified for a job.
The most famous bearer of the surname Knavs today is Melanija Knavs Trump, the wife of US President Donald Trump.