I have recieved the grades for my PhD, and the defense is yet to be done. I have a magna cum laude for the course work, and a cum laude for my dissertation. Do I have an academic career in Germany if I end up with a cum laude for the PhD? Is there any way I can salvage a magna cum laude? The defense remains. Neither of my supervisors read any of my drafts. They said that I should submit, and then gave me cum laude, which is the second-to-lowest in Germany. (There is rite, cum laude, magna cum laude, summa cum laude.)
Well, yes, but also no.
Permanent academic positions that are not professorships are relatively rare in Germany. Since most researchers want to eventually have a permanent position, it is in the interest of all long-term researchers to eventually become "berufungsfähig" (suitable for becoming a tenured associate or full professor).
The vast majority of the universities are public in Germany, and hence the laws of the respective state regulate hiring in the universities. All(?) "Landeshochschulgesetze" (law on higher education) list mandatory requirements for candidates for professor positions.
For instance, the respective law of the state of North-Rhine Westfalia (that has the largest population) states as a requirement:
besondere Befähigung zu wissenschaftlicher Arbeit, die in der Regel durch die Qualität einer Promotion nachgewiesen wird;
In English, this means that the candidate must show a substantial/remarkable/special ability to research work, which is normally indicated by the quality of the PhD. Given that PhDs are thesis-only in Germany (while the defense may also include more general questions about the field of work), this means that the PhD thesis should be particularly good and have a corresponding grade. The state of Lower Saxony has in their law that the PhD should be above average, and given that there are four passing grades, "cum laude" is probably below average.
Now what does should mean concretely? It means that if a hiring committee wants to hire somebody with a bad PhD thesis, they risk the overall hiring process being delayed or even canceled. There may be objections, candidates not snatching the precious professorship may sue, or the respective ministry of education may intervene or simply refuse to send the offer letter to the successful candidate. There have surely been cases of pea counting as far as the formalities of candidates to be hired are concerned in the past, and this adds to the risk. Hiring committees and universities will probably take the risk if there is a very good and demonstratable reason for why the candidate is excellent despite a bad PhD thesis, depending on their legal interpretation of the should and how much they are willing to risk it. In any case, certainly, those candidates with a good PhD thesis have a substantial head-start, and it's quite hard to catch up for candidates with a grade lower than "Magna Cum Laude".
Having said this, there are also other permanent academic positions, such as in Fraunhofer or Max Planck institutes that may or may not have similar requirement. So a Cum Laude may not be a big deal if they want you for a different reason.
I don't know the specifics of Germany, but in general an academic career doesn't depend that much on the PhD, let alone on the level of honor given to the degree.
If you apply for postdoc positions at the international level, people are unlikely to even look at the level of honor because these differ a lot by country so they do not provide a standard objective indication. Traditionally the publication track record is considered more important, and of course how well your profile fits the specifics of the job.
If you get a postdoc position and do a good job during the postdoc, nobody will care about the PhD level of honor.