The Center for Family Business (located at the KMU-HSG) has published the Global Family Business Tax Monitor.
This project in collaboration with EY compares inheritance taxes in the case of family business succession in 69 (whereof 37 European) countries worldwide.

The results are available at http://familybusinesstaxindex.com/
These 37 European countries that are covered the project:
Austria / Belgium / Bosnia and Herzegovina / Bulgaria / Croatia / Cyprus / Czech Republic / Denmark / Estonia / Finland / France / Germany / Greece / Hungary / Iceland / Ireland / Isle of Man / Italy / Latvia / Lithuania / Luxembourg / Malta / Netherlands / Netherlands Antilles / Norway / Poland / Portugal / Romania / Russia / Slovak Republic / Slovenia / Spain / Sweden / Switzerland / Turkey / Ukraine / United Kingdom