This year's partner country is the Republic of Ireland.
The festival will kick off with a concert by the Irish Baroque Orchestra on 23 September, and an Irish youth orchestra will also perform a week later. An Irish Corner will be set up in Varaždin as part of a supporting programme..
Irish Ambassador Ruaidhri Mark Dowling said it was an honour for his country to be the partner.
So far, the partner countries have been Germany, Czech Republic, Poland, Slovakia, Israel, Austria, the Russian Federation, Italy, France, Spain, Hungary, Japan and Sweden.
"The Varaždin Baroque Evening Festival is the most important music and stage event in central Croatia, founded in 1971, and today, as a specialised festival of early music, it is one of the most eminent festivals of its kind in the world. The festival is under the permanent auspices of the President of the Republic of Croatia, and the Ministry of Culture of the Republic of Croatia awarded it national significance 20 years ago," the festival's website says.