There is so much talk about this topic so I decided to analyse this question in a broader scope. The most recent fact is that Bundesliga will overtake Seria A in the UEFA Coefficient System and it'll affect the CL spots given to the both leagues. Leaving aside UEFA's system, what is the most successful league in the world? There are two leading leagues in the form of Seria A and La Liga who have won more European titles than any other league. But here I'll focus about the domestic league rather than the European competition.
2 Spanish
3 Italian
4 German
5 French
6 Turkish or Russian league
these are the best leagues in Europe